Added Auto-Discovery & other enhancements

Added Automatic Network discovery mechanism.
Moved background tasks to a 'headless' fragment.
Fixed margin for command Fragment.
Added some/better support for Orientation changes (so state is retained/updated).
Moved Receiver state (mute, volume, power status, etc) to an 'info' struct, rather than in the Eiscp class.
Restored 'static' nature of most Eiscp class methods.