Add a documentation preprocessing stage

Tools/Config/config.json

@@ -13,6 +13,7 @@
         "packageES6DevFolderName": "packageES6Dev",
         "playgroundDirectory": "../../Playground/",
         "intellisenseFile": "babylon.d.txt",
+        "documentationFile": "documentation.d.ts",
         "intellisenseSources": [
             "../../dist/preview release/babylon.d.ts",
             "../../dist/preview release/gui/babylon.gui.d.ts",

Tools/Gulp/gulpfile.js

@@ -90,4 +90,4 @@ gulp.task("npmPackages", gulp.series("npmPackages-all"));
 /**
  * The default task, concat and min the main BJS files.
  */
-gulp.task("default", gulp.series("cleanup", "tsLint", "importLint", "circularDependencies", "typescript-all", "intellisense", "typedoc-all", "tests-all"));
+gulp.task("default", gulp.series("cleanup", "tsLint", "importLint", "circularDependencies", "typescript-all", "intellisense", "documentation", "typedoc-all", "tests-all"));

Tools/Gulp/tasks/gulpTasks-intellisense.js

@@ -18,4 +18,10 @@ gulp.task("intellisense", function() {
         .pipe(replace(/^\s* _/gm, "private _"))
         .pipe(replace(/^\s*_/gm, "private _"))
         .pipe(gulp.dest(config.build.playgroundDirectory));
+});
+
+gulp.task("documentation", function() {
+    return gulp.src(config.build.intellisenseSources)
+        .pipe(concat(config.build.documentationFile))
+        .pipe(gulp.dest(config.build.outputDirectory));
 });