created initial support for DnD for the folders.
Resolved conflicts.

Conflicts:

src/main/java/org/ednovo/gooru/client/mvp/shelf/collection/tab/resource/item/CollectionEditResource.css

src/main/java/org/ednovo/gooru/client/mvp/shelf/collection/tab/resource/item/CollectionEditResourceCBundle.java
Merge branch 'dev-branch' of https://github.com/Gooru/Gooru-Web into dev-branch
Reverted DnD changes made for re-ordering
Merge branch 'dev-branch' of https://github.com/Gooru/Gooru-Web into dev-branch
Merge pull request #478 from VinRudramurthy/dev-branch

Reverted DnD changes.