[WIP] Added ToJArray to handle the conversion to IEnumerable<T> into RavenJArray.
- HeaderToObject methods to handle NameValueCollection conversions.
- Fixed: RavenJValue constructor for Guid sets it as string.
- Updated Lightweight client to use the RavenJObject instead of NameValueCollection.
- Updated tests that assumed interfacing with NameValueCollection instead of RavenJObject.
- Unified the creation of MetadataWithETag using the extension method.
- Updated controllers result to use GetMessageWithObject and serialization.