resourceloader: cache minified user and site modules
* Add support for a '/* @nomin */' annotation in ResourceLoader. If present in
JavaScript or CSS, the code will not be minified or cached. This allows
modules like the ResourceLoaderUserTokensModule to declare themselves unfit
for minification / caching without requiring a complicated refactor.
* Make ResourceLoader::filter() static, at the cost of not having minifier
errors in the ResourceLoader log bucket. (They will continue to be logged as
exceptions, however).
Change-Id: Ic1d802ee20565e61046bfbd8fd209bc56a4cbd6c