* refactoring assets management code
* finalizing refactoring of assets management
* various code review of new assets management code
* fix#2281
* fix#1961
* fix#1293
* fix#1275
* fix update scheduler timing logic
* forward compatibility (to be removed once 1.11+ is widespread)
* more codereview; give admins ability to specify own assets.json
* "assetKey" is more accurate than "path"
* fix group count update when building dom incrementally
* reorganize content (order, added URLs, etc.)
* ability to customize updater through advanced settings
* better spinner icon
.jshintrc's otion-set is a personal choice, merely a suggestion.
Beside that, it includes some common globals for specific browsers, so
there's no need to set the globals in every .js file.
In order to force strict coding, "use strict" directive was added into
every .js file.
