Improve writing style and formatting in README

This also updates links to use HTTPS where possible.

readme.md

@@ -1,64 +1,66 @@
-Babylon.js
-==========
+# Babylon.js
 
-Getting started? Play directly with the Babylon.js API via our [playground](http://www.babylonjs.com/playground). It contains also lot of simple samples to learn how to use it.
+Getting started? Play directly with the Babylon.js API using our [playground](https://playground.babylonjs.com/). It also contains a lot of samples to learn how to use it.
 
 [![Build Status](https://travis-ci.com/BabylonJS/Babylon.js.svg)](https://travis-ci.com/BabylonJS/Babylon.js)
-[![Average time to resolve an issue](http://isitmaintained.com/badge/resolution/babylonJS/babylon.js.svg)](http://isitmaintained.com/project/babylonJS/babylon.js "Average time to resolve an issue")
-[![Percentage of issues still open](http://isitmaintained.com/badge/open/babylonJS/babylon.js.svg)](http://isitmaintained.com/project/babylonJS/babylon.js "Percentage of issues still open")
+[![Average time to resolve an issue](https://isitmaintained.com/badge/resolution/babylonJS/babylon.js.svg)](https://isitmaintained.com/project/babylonJS/babylon.js "Average time to resolve an issue")
+[![Percentage of issues still open](https://isitmaintained.com/badge/open/babylonJS/babylon.js.svg)](https://isitmaintained.com/project/babylonJS/babylon.js "Percentage of issues still open")
 
 **Any questions?** Here is our official [forum](http://www.html5gamedevs.com/forum/16-babylonjs/) on www.html5gamedevs.com.
 
 ## CDN
-- https://cdn.babylonjs.com/babylon.js
-- https://cdn.babylonjs.com/babylon.max.js
-- https://cdn.babylonjs.com/babylon.worker.js
 
-Additional references can be found on https://cdn.babylonjs.com/xxx where xxx is the folder structure you can find in the /dist folder like https://cdn.babylonjs.com/gui/babylon.gui.min.js
+- <https://cdn.babylonjs.com/babylon.js>
+- <https://cdn.babylonjs.com/babylon.max.js>
+- <https://cdn.babylonjs.com/babylon.worker.js>
 
-For preview release you can use the following ones:
+Additional references can be found on <https://cdn.babylonjs.com/xxx> where `xxx` is the folder structure you can find in the /dist folder like <https://cdn.babylonjs.com/gui/babylon.gui.min.js>
 
-- https://preview.babylonjs.com/babylon.js
-- https://preview.babylonjs.com/babylon.max.js
-- https://preview.babylonjs.com/babylon.worker.js
+For the preview release, use the following URLs:
 
-Additional references can be found on https://preview.babylonjs.com/xxx where xxx is the folder structure you can find in the /dist/preview release folder like https://preview.babylonjs.com/gui/babylon.gui.min.js
+- <https://preview.babylonjs.com/babylon.js>
+- <https://preview.babylonjs.com/babylon.max.js>
+- <https://preview.babylonjs.com/babylon.worker.js>
 
-## NPM
+Additional references can be found on <https://preview.babylonjs.com/xxx> where xxx is the folder structure you can find in the /dist/preview release folder like <https://preview.babylonjs.com/gui/babylon.gui.min.js>
 
-BabylonJS and its modules are published on NPM with full typing support. To install use
+## npm
 
-```
+BabylonJS and its modules are published on npm with full typing support. To install, use:
+
+```text
 npm install babylonjs --save
 ```
 
 This will allow you to import BabylonJS entirely using:
 
-```
+```javascript
 import * as BABYLON from 'babylonjs';
 ```
 
 or individual classes using:
 
-```
+```javascript
 import { Scene, Engine } from 'babylonjs';
 ```
 
-If using TypeScript, don't forget to add 'babylonjs' to 'types' in tsconfig.json:
+If using TypeScript, don't forget to add 'babylonjs' to 'types' in `tsconfig.json`:
 
-```
-    ....
+```json
+    ...
     "types": [
         "babylonjs",
         "anotherAwesomeDependency"
     ],
-    ....
+    ...
 ```
 
-To add a module install the respected package. A list of extra packages and their installation instructions can be found on [babylonjs' user at npm](https://www.npmjs.com/~babylonjs).
+To add a module, install the respective package. A list of extra packages and their installation instructions can be found on the [babylonjs user on npm](https://www.npmjs.com/~babylonjs).
 
 ## Usage
-See [Getting Started](http://doc.babylonjs.com/#getting-started)
+
+See [Getting Started](https://doc.babylonjs.com/#getting-started):
+
 ```javascript
 // Get the canvas DOM element
 var canvas = document.getElementById('renderCanvas');
@@ -96,26 +98,29 @@ window.addEventListener('resize', function(){
     engine.resize();
 });
 ```
+
 ## Preview release
 
 Preview version of **3.3** can be found [here](https://github.com/BabylonJS/Babylon.js/tree/master/dist/preview%20release).
 If you want to contribute, please read our [contribution guidelines](https://github.com/BabylonJS/Babylon.js/blob/master/contributing.md) first.
 
 ## Documentation
+
 - [Documentation](https://doc.babylonjs.com)
 - [Examples](https://doc.babylonjs.com/examples)
 
 ## Useful links
 
- - Official web site: [www.babylonjs.com](https://www.babylonjs.com/)
- - Online [playground](https://playground.babylonjs.com/) to learn by experimentating
- - Online [sandbox](https://www.babylonjs.com/sandbox) where you can test your .babylon and glTF scenes with a simple drag'n'drop
- - Online [shader creation tool](https://www.babylonjs.com/cyos/) where you can learn how to create GLSL shaders
- - 3DS Max [exporter](https://github.com/BabylonJS/Exporters/tree/master/3ds%20Max) can be used to generate a .babylon file from 3DS Max
- - Maya [exporter](https://github.com/BabylonJS/Exporters/tree/master/Maya) can be used to generate a .babylon file from 3DS Max
- - Blender [exporter](https://github.com/BabylonJS/Exporters/tree/master/Blender) can be used to generate a .babylon file from Blender 3d
- - Unity 5 [exporter](https://github.com/BabylonJS/Exporters/tree/master/Unity%205) can be used to export your geometries from Unity 5 scene editor(animations are supported)
- - [glTF Tools](https://github.com/KhronosGroup/glTF#gltf-tools) by KhronosGroup
+- Official web site: [www.babylonjs.com](https://www.babylonjs.com/)
+- Online [playground](https://playground.babylonjs.com/) to learn by experimentating
+- Online [sandbox](https://www.babylonjs.com/sandbox) where you can test your .babylon and glTF scenes with a simple drag'n'drop
+- Online [shader creation tool](https://www.babylonjs.com/cyos/) where you can learn how to create GLSL shaders
+- 3DS Max [exporter](https://github.com/BabylonJS/Exporters/tree/master/3ds%20Max) can be used to generate a .babylon file from 3DS Max
+- Maya [exporter](https://github.com/BabylonJS/Exporters/tree/master/Maya) can be used to generate a .babylon file from 3DS Max
+- Blender [exporter](https://github.com/BabylonJS/Exporters/tree/master/Blender) can be used to generate a .babylon file from Blender 3d
+- Unity 5 [exporter](https://github.com/BabylonJS/Exporters/tree/master/Unity%205) can be used to export your geometries from Unity 5 scene editor(animations are supported)
+- [glTF Tools](https://github.com/KhronosGroup/glTF#gltf-tools) by KhronosGroup
 
 ## Features
-To get a complete list of supported features, please visit our [website](http://www.babylonjs.com/#specifications).
+
+To get a complete list of supported features, please visit our [website](https://www.babylonjs.com/#specifications).