adding AssetLocationUtility to create assets from files in a directory, also removing CaplinJsFilesetFactory
changing NodeJsBundlerPlugin  to use AssetLocationUtility
changing bundler plugins and bundlable nodes to move away from using the AssetFileFactory and instead use AssetLocationUtility
deleting fileAssetFactory and changing AssetLocationUtility so it's used through BRJS and BRJS just proxies through to it. AssetLocationUtility now keeps the cache of AssetFiles too.
refactoring AssetContainer and AssetLocation interfaces so AssetFiles allow access to AssetLocations and AssetLocations allow access to AssetContainers
tidy up after previous refactor of interfaces, moving shared logic between JsLib and AbstractAssetContainer back into AssetContainerLocations
removing all the TODOs for MockRootNode which wi always have empty stub methods
adding some very basic JavaDoc
removing a TODO that has been done
removing File param to AssetLocationUtility.getAssetFiles since the utility can call .dir() itself
Merge pull request #251 from BladeRunnerJS/bundlerRefactoring

Bundler refactoring