change wording for !join (suggested by Makiavel)
Clean up var.illegal_joins during !start, fix related !join bug

This patch fixes a bug in !join that caused new entries to be created in
the var.illegal_joins dictionary for every joining player because of a
missing check to see if the player's cloak is in the dictionary at all.

It also adds logic to !start to remove entries from the
var.illegal_joins dict if they currently have a value of 0, since these
entries are no longer relevant.

These changes together make !eval var.illegal_joins far more useful for
getting a list of *just* stasised players.
Add empty declarations and checks to partly fix START_WITH_DAY.

This commit adds some variable declarations and other minor things so
that setting var.START_WITH_DAY to 1 doesn't cause errors. This commit
doesn't actually fix that gamemode completely, since I'm still
pondering how best to make the game notify people of their roles when
the game starts in this mode, but it's a good start.
Change the default value of IDLE_STASIS_PENALTY to 1.

This has been the effective default in #wolfgame for a few days, and
the channel seems to have had few complaints about it and a few
positive comments, so I'm switching it to default. Seconded by dwfreed.
Merge pull request #2 from skizzerz/wording

change wording for !join (suggested by Makiavel)
Re-add missing . at the end of !retract response.

Minor change requested by someone in #wolfgame a while ago. The old
!retract message ended in a period, and it's still there in the logger
message, but the new in-channel message didn't have one.
Change message when wolves win to mention injury (closes #1)

The message about wolves winning was unclear that the comparison is
between wolves and uninjured villagers, which caused confusion a few
times because people thought the game ended due to a bug. This commit
changes the message to avoid this confusion.
Adding a . to the end of the join message.

Requested by nyuszika7h in #wolfgame-dev.
Change playercounts for drunk, traitor, and wolf2

Per discussion in #wolfgame-dev, this commit changes the playercounts at
which drunk, traitor, and wolf2 are introduced. It removes drunk from 6p
and 7p games (moving it from 6 to 8), adds traitor to 8p and 9p games
(moving it from 10 to 8), and removes wolf2 from 8p and 9p games (moving
it from 8 to 10).

Or, in other words, it moves drunk later and switches traitor and wolf2.

Statistics on the effect of these two changes can be measured
independently, because they affect different ranges of games.

If this commit causes gameplay or other issues, feel free to revert it.