Implement seen and timezone plugins

[jayvdb]

Test and add these plugins to the default config

• https://github.com/Appleman1234/arisu/tree/master/Seen
• https://github.com/Appleman1234/arisu/tree/master/Time
• https://github.com/redwallhp/errbot-timezones

Something a bit fun the play with, at least in test/offtopic rooms , and combined help people understand why someone isnt able to do a review of their PR, cause they are probably asleep.