Make a list of variants that either base or avalon could use
Add format_mission_results

This catches a subtle bug: !missions won't show how many fails on the
4th mission in a 7+ player game
get_loyalty_info: always show roles

It will soon be possible for Base games to have roles, and it does no
harm to use the same code here.
tell_loyalty_to: Always check specific role even in Base games

We will soon have Base games with roles and this will help.
Implement Reversers

Closes #24
who_spies: Always show all roles

Base games have roles now.
Merge pull request #30 from an1itdp01y/reverser

Reverser