Added support for Symbian Mediakeys

support for Symbian Mediakeys. Usually volume up/down, but it also
support play/stop etc. if user has "remotecontrol" provided with nokia
headset.
using native keycodes instead of my own as symbian mediakeys
fixed tabs, and using NativeKeys instead of forwarding keyevent though qapplication
Fix indents and use native keys.
Merge pull request #161 from Summeli/master

Added support for Symbian Mediakeys