Migrations + Teams + possible SVN Conflicts

This is a special case for our team, too. We just broadcast that
there's a new migration, and try to get it checked in before all the
other changes. In the event of a collision, the person with the last
check-in just renames the migration. SVN renaming is easy (I am still
recovering from post-traumatic stress related to many years of CVS

We had thought this might go away when we all started to work off the
same central development database (assuming that the migrate task got
its number from the schema version table), but it seems to be just
scanning the migration files.