Added validation
Changed owners to members for users/groups/networks.
Added read/write/admin permissions to memberships.
Added JavaDoc comments to all RESTful methods.
Added validation to all RESTful methods.
Added isPublic flag to networks, set to false by default when creating networks.
Updated Test Create Database unit test.
Add REST call to accept/decline a request.
Fixed bug where user page was loading the user twice (because it loaded the same user as the one logged in).
Merge branch 'origin/develop'

Conflicts:
	src/main/java/org/ndexbio/rest/services/GroupService.java
	src/main/java/org/ndexbio/rest/services/NetworkService.java
	src/main/java/org/ndexbio/rest/services/UserService.java