Fixed a bug where minions that died during vanish would cause a crash.

Closes #71
Merge remote-tracking branch 'origin/master'
Fixed a placement bug with Leeroy Jenkins.  Closes #73

When Leeroy wasn't placed at index 0, the second Whelp was getting a
weird index.

Also changed the name of the exception raised when a strange index is
encountered.
Fixed a bug where redemption on a full board crashed the game.

Closes #74
Merge pull request #32 from danielyule/master

Merge