create event emitter in Room instead of Connections
use directly event emitter for inter-module communication (used to pass
through Connections)
use events to manage local video (and getUserMedia)
use showdown.js to format textchat messages in markdown
auto translate urls to links and set target='_blank' to all links
Merge pull request #43 from Paulloz/eventemitter

Communication design enhancements
Merge pull request #44 from Paulloz/textchatformatting

Format text chat messages with Markdown.
Auto-translate urls to Markdown link.
Set all link's target attribute to _blank.
Fixes #9

Conflicts:
	src/frontend/modules/textChat.coffee
Display a message when the camera is blocked by the browser.
Fixes #39 user feedback when camera is blocked.
Remove tab on empty line.
Merge pull request #46 from azziel149/media

User feedback when camera is blocked by the browser.