Resources are displayed according to resource categories defined for nroer

* As we defind 8 different caegories for resources in NROER, Now resources are getting displayed according to these defined categories. such as currently we have resources having types:
Interactives,Documents, Images, Videos, Audios etc

* ```educationaluse``` is the AT defined for defining these types for indivisual resources.

* queries added in ```browse_resource.py``` to fetch these types of resources according to the attributes defined for each of the resource

* "File" app doesnt display these categories. since this is nroer resources specification only for "Browse Resurce" app.

* Now in Browse Resources we can see the resources are categorized into these types in separate tabs.

* As soon as we receive the set of resources of other remaining 3 types will also categorized them in future. 

* Also removed the "collection" tab from Browse Resource since its unecessary in this context.