add `clientVariable` option to `AngularTemplatesAsset` and update readme
AngularTemplates asset should compile jade
fix recursing directories for angular templates & add root option
fix backwards compatibility with previous version of angular-templates assets+

* Update readme with examples
* Change `root` option to `templateCacheDirname`: more descriptive
Updated browserify version

Also added support for defining transforms and externals on
BrowserifyAsset
Switched from bundle.require to bundle.add for entry point file
A more flexible way to define requires
Browserify filename optional
More robust watching
No error thrown if asset doesn't exist
Better watching on less files