Added Notification and Subscription clients. Updated library dependencies to the latest versions.
Minor fixes to ensure .NET 3.5 client compiles, and .NET 4.0+ tests run.
Added references DTO.
Added a couple of console test for Message's references. Updated Message client return type to MessageEnvelope.
Moved common ConsoleTest classes to a shared project. Reviewed GroupClient.
Reviewed Invitation client.
Moved Invitation client default configuration to a separate partial class. Minor variable rename for Message client.
Updated Notification client to return expected type.
Updated Notification client to accept Relation array as parameter.
Renamed Relationship to RelationshipEnvelope. Added Page DTO for Search client results.
Added GetByTopicId in Message client.
Refactored JsonServiceClient common properties into a shared project.
Added .NET 4.0 and .NET 4.5 project shims. Rearranged solution's project folders back into `src` and `tests`.
Added user's web preferences DTO. Reviewed User DTOs.
Added `GetAllBookmarked` and `GetAllLiked` undocumented methods.
Updated Readme and ReleaseNotes information.
Updated User DTO interface visibility. Updated User DTO class UML diagram.
Moved shared core test project into the `/tests` folder. Updated client projects' assembly and assembly file version. Updated release notes.
Merge branch 'develop'