Add file cache implementation
Add file cache to provider
Move cache driver factory to separate method in cache resource provider
Add parent folder creation before writing to a file
Add instantiation test for file cache driver and fix found typos
Merge pull request #6 from ob-ivan/feature/fileCache

Implement file cache
Merge branch 'master' into feature/smartUpload

Conflicts:
	src/Ob_Ivan/DropboxProxy/ResourceProvider/CacheResourceProvider.php