fix PEP8 W291 and W293 (trailing whitespace)

extra/example.py

extra/games.py

extra/rss.py

extra/wikinews.py

guppy

irc.py

plugins/__init__.py

plugins/admintools.py

plugins/auth.py

plugins/blockbot.py

plugins/ctcp.py

plugins/ddg.py

plugins/dns.py

plugins/dynacode.py

plugins/google.py

plugins/help.py

plugins/isitup.py

plugins/karma.py

plugins/ping.py

plugins/plugintools.py