Rearrange buckets in a full game

[ramaxfield-git]

Currently, the following situation can easily arise:

• A game has buckets Male and Female (for instance) with an additional No Preference signup option.
• No Preference players are arbitrarily distributed into buckets.
• The game is full and has a waitlist.
• GMs cast the game according to surveys, with some No Preference players being given characters in a bucket other than the one they were arbitrarily sorted into.
• A No Preference player arbitrarily sorted Male, but cast in a Female role from the survey, drops. Intercode pulls the first waitlister who selected Male, and they will not play the only available role

Currently, GMs aren't able to rearrange players into the buckets of the roles they've actually been cast in, because:

• you cannot leave a player with no bucket, even temporarily
• you cannot move a player into a bucket that is full

Note that the freezing buckets feature does not solve this problem because the problem is different.

Request: Solution to this problem, could be:

• checkbox and button option to switch two players' buckets
• drag and drop or some other kind of interface where you can make as many changes as you like and the system just validates them when you hit save. (To be fancy, this could also validate as you go - say, a rectangle representing a bucket is green if it contains the right number of player names and red if not - but validating on save and allowing temporary invalid states during the moving-around phase would be the thing.)
• something else