For sorting dropdown UI has been added.
Merge branch 'dev-branch' of https://github.com/Gooru/Gooru-Web into dev-branch

Conflicts:
	src/main/java/org/ednovo/gooru/client/mvp/classpages/studentView/StudentAssignmentView.java
Resolved conflicts and updated sort dropdown UI in teach.
Merge branch 'dev-branch' of https://github.com/Gooru/Gooru-Web into dev-branch

Conflicts:
	src/main/java/org/ednovo/gooru/client/mvp/classpages/edit/EditClasspageView.java
Merge pull request #539 from shivalinga/dev-branch

For sorting dropdown UI has been added.