Change path name semantics.

Paths do not end with slash.
Namespacing FileSystem object.
File and Folder classes.

Extracting File and Folder classes from RAML repository and introducing
functions on FileSystem that generate File and Folder classes backed by
your storage of choice (like, local or remote or totally fake)!
Removing RamlRepository.

Now we pass around Folder and File objects and it's cool.
Remove folders.
Merge branch 'epics/folder-support-917228' into features/delete-folder-64254754

Conflicts:
	app/scripts/services/raml-repository.js
	test/spec/raml-repository.js