Undo release

[Dodgers]

For those of you with access to the Admin Control Panel (I think we all do, but not positive about Jake and Jim, though they should probably have access if they don't, let me know guys), I added a feature to undo an erroneous release (such as Bren's earlier this week).

It's pretty straightforward, just select the transaction and it will take care of the rest. There is some testing to take them off waivers if necessary and also some user error stuff (ie you can't go back and undo a release after someone else signs them, you'd still have to go through me for that). Note that a post will be made with your username automatically to notify the league of the reversal.