New message view

Here comes the new message view.

Features:
 - Faster chat view widget (QGraphicsView based)
 - Search for text
 - Smiley support
 - Full text selecting and copying
 - Sending and displaying typing notifications
 - Marker line on last seen message
 - Custom time stamp format

Fixes:
 - #59 Copy selected text with smileys from message label doesn't work
 - #62 Reimplement Message Display widget
 - #64 Custom time stamp format
 - #99 Can't highlight more than 1 line at once

![screen](https://cloud.githubusercontent.com/assets/329423/3117432/cf107caa-e72c-11e3-99fb-857dae6f2ac2.png)

PS: This replaces the old push request #110 .