Finish web.py API

Now to add more Shorteners/Pastebins...
Add more URL shorteners

Add more URL shorteners
Also, make web.expand try to scan for a URL shorter to use
If it doesn't have a dedicated one, it just follows the link
Merge pull request #5 from neersighted/web-fuckery

Web Fuckery
Use requests's allow_redirects=False parameter instead of checking request.url. Also, fall back on the default shortener expansion using an if check instead of creating a new Shortener for every failed match.
Update plugins to use new web shortening and paste api
Add @asyncio.coroutine to a ton of plugins

Note: also updates some plugins to new format (inp -> text, multiple @hook.commands -> one hook)