urls added for json-rpc to fetch the resources with its metadata
'jsonrpc' included in INSTALLED_APPS list in settings
jsonrpc method 'resources' added in this view
updated url field with their download links for all resources
Added the url(resource link) in returned json for rpc method
url field for resources updated with downloadable link having extension
added 'django-json-rpc' package
bug resolved in accessing mime_types of resources
Merge pull request #944 from sunnychaudhari/work

Implemented "django-json-rpc" for fetching resource & its metadata.
multiple subgroup can be added
Merge branch 'mongokit' of https://github.com/gnowledge/gstudio into mongokit