Adding support for ArrayableInterface and JsonableInterface in Message Bag.

Signed-off-by: Ben Corlett <bencorlett@me.com>
Tweaking order of implementations for Message Bag.

Signed-off-by: Ben Corlett <bencorlett@me.com>
Merge pull request #129 from bencorlett/master

Adding support for ArrayableInterface and JsonableInterface in Message Bag