Tweak message format to flow a bit better.

Including the card or board name with the link feels a bit more
semantic than simply saying "Card" at the end. By going to the
effort of customizing the position of this link in each message,
we can also make it feel a bit more natural.
Handle moveCardToBoard.
Properly report both checking and unchecking.
Merge pull request #2 from wdaher/master

Update bot format slightly.