Store pending messages in list.

This avoids copying elements around as they are added to the back and fetched from the front.
Use multiple channels for caching of buffers.

This should help in high-concurrency situations but needs more profiling.
Fixed API without handle support.
Gofmt.
Fixed chat background image.
Changed sent and delivered icons.
More chat delivery state icon changes.
Include number of chat message in hub statistics.
Also cache buffers when encoding broadcast JSON.
Rebuilt translations.
Only show  rightslide when in a room.
Do not restore chat on room switch.
Added buddy classes to let css react on component hide/show stuff.
Implemented buddy list toggle icon.
Fixed bar styles.
Added chat maximize support.
Fixed responsive width. Not optimal but better than before.
Fixed help style bottom margin.
Text shadow fixes.
Implemented page loader.
Implemented page loader.