Prematch replaced with /ready command

See TF-versions.txt. No more pm, and serverinfo pm time is irrelevant
now.  Players must type /ready for the game to start. Lots of alignment
updates.

New serverinfo statuses set by mod: Prematch, Countdown, Match, Standby.

Don't use ceasefire yet as it's broken. Also I don't think regular,
non-clan mode works yet. Soon.