Register 12 new JSON filenames/extensions (#4053)

Added:
* .avsc
* .gltf
* .htmlhintrc
* .jscsrc
* .jslintrc
* .jsonl
* .tern-config
* .tern-project
* .tfstate
* .tfstate.backup
* .webapp
* .webmanifest

samples/JSON/manifest.webapp

@@ -0,0 +1,19 @@
+{
+	"version": "1.0",
+	"name": "demo",
+	"description": "demo",
+	"launch_path": "/index.html",
+	"icons": {
+		"128": "/res/icon.png"
+	},
+	"developer": {
+		"name": "Cocos2d-html5",
+		"url": "http://cocos2d-x.org/"
+	},
+	"default_locale": "en",
+	"installs_allowed_from": [
+		"*"
+	],
+	"orientation": "portrait-primary",
+	"fullscreen": "true"
+}