Adds a chance of syndiborg to the staff of change.

Odds of syndiborg are 5%, odds of normal borg are now 11.666...%, down from 16.666...%

syndiborgs spawn with their default lawset, which means that they can (and almost certainly will) try to kill everyone if left to their own devices
Merge pull request #2653 from Incoming5643/syndiborgchance

Adds a chance of syndiborg to the staff of change