Fix an install error in Windows due to the Twisted Windows executable changing name from twistd.py to twistd.exe.
Fix an install error in Windows due to the Twisted Windows executable changing name from twistd.py to twistd.exe.

titeuf87/evennia,feend78/evennia,jamesbeebop/evennia,titeuf87/evennia,jamesbeebop/evennia,titeuf87/evennia,feend78/evennia,jamesbeebop/evennia,feend78/evennia,titeuf87/evennia,feend78/evennia