Add OSX notification support
Moved get_conv_name to hangups.utils
Made sender_name a subtitle instead of a prefix
Merge pull request #13 from mtomwing/osx-notifications

Add OSX notification support
Remove unnecessary print call
Fix backslash/quote issues with gbus notifications
Implement sending segmented chat messages
Implement sending eastereggs like /ponies and /pitchforks
Refactor chat message segment support

Make methods supporting segments the default, add a ChatMessageSegment
class, and cleanup.
Sync with upstream