Added CPE MessageTypes support.

As the title says. Did not add support for Top left because it would overlap the debug message that already exists there. Also, I did not include any way for the announcement to disappear after a said time, as I'm not sure how it should be done. 

Should be noted also that the announcement's placement is hard to get correct. I have a working example, but it may be off center for some text.

You may test if you like on my server, with commands /br1, /br2. /br3, and /announcement.

Here's a picture of it in action:
![201410011389345796](https://f.cloud.github.com/assets/1891692/1885846/e4e3c9c2-79d8-11e3-97b3-1f8093108282.png)