Removed placeholder messages for Castform/Cherrim transformation

Added [msg] handler for client to check for and display the message.
Removed placeholder message for Focus Band
Thousand Arrows now hits all adjacent foes and targets with Fly, etc.

Also updated the description of the move.
Added [msg] handler for Meloetta's transformation
Merge pull request #1279 from ascriptmaster/move-fixes

Various move fixes