Add minimum notification interval, channel ignores

This release adds the ability to:

• set a minimum notification interval, so pushbullet doesn't spam you as hard,
• channel ignores, to keep the number of unnecessary notifications down

If anyone has more ideas for better filtering and spam reduction, please let me know!

First working release.

0.2.0

Merge branch 'master' of github.com:LeftyBC/weebullet