migrations: skip migration files that end with a tilde
migrations: skip migration files that end with a tilde

some editors like vim create backup files by appending a tilde to the
filename. And this creates some annoyances when testing migrations on
development box. So this commit changes migrations so it skips files ending
with a tilde.

devpanel/serverlink,devpanel/serverlink,devpanel/serverlink,devpanel/serverlink,devpanel/serverlink