Refactored bot to it's own package

Moved bofhwitsbot.go and config.go to a subpackage, bofhwits.go is now
a simple runner.  Hopefully this sensibly separates bot logic from
program startup and config file handling.
Trying to object orient bofhwitsbot...
Fixed.  Converted functions acting on BofhwitsBot to take a pointer
Merge pull request #1 from amauragis/refactor

Refactor