I don't always get new commands, but when I do, it's a MEME command.

Hi David. First pass at adding a simple meme command.

### MEME COMMAND
usage: `/meme <meme-type> <top-line> <bottom-line>`
eg: `/meme aa Why-is-JabbR-offline? Aliens`

Included are some unit tests and a simple method which ends up calling the `Send(..)` method.

SIDE QUIRK: I noticed the test classes in `JabbR.Tests` where missing the 's' so I added that.