Generic way to use notification services

From python:

import notifiers

pushover = notifiers.get_notifer('pushover')
pushover.notify(title='Foo', message='Bar', token='TOKEN')

pip install notifiers

Get a notifier:

pushover = notifiers.get_notifer('pushover')

Or:

pushover = notifiers.providers.Pushover()

Send a notification:

pushover.notify(token='TOKEN', title='Foo', message='Bar')

Get notifier metadata:

print(pushover.metadata)

{
    "url": "http://..."
    "description": "A Great notifier!"
    ..
}

• Many more providers
• CLI
• Environment variable support
• Docs

I wanted to avoid the whole unicode issue fiasco if possible, but there's not real constraint in adding python 2 support. If there's an overwhelming desire for this, i'll do it. Probably.