store chanid as unsigned int in EITScanner
Optimize reschedules from the EITScanner (low hanging fruit only)

Use watchdog based reschedules only for passive scan. In active scan
we switch to another channel soon enough.
Since [cbb8eb1ee] reschedules can be limited to changed parts of the
guide. We store the sourceid the EITscanner is active on since
[3c3dd7c5], hand it over to the scheduler.
Optimize EIT reschedules by limiting them to changed schedule parts.

Only reschedule all transports if we've handled EIT schedule other.
Only reschedule up to max(starttime).
extend normalization of AC-3, DTS and E-AC-3 signalling
Remove hack to normalize H.264 signalling for ITV HD
attempt to unbreak ASIRecorder past [023b90f4]
Playback: Cut the Manual zoom increment in half, for finer-grained control.
Improve the Manual Zoom experience during video playback.

Add new ZOOM* actions to the TV Playback context (with no predefined
key bindings), to get away from overloading other key bindings.  The
old overloads are left intact, but the ZOOM actions are preferred.

Double the maximum zoom in/out factors.

Remove the behavior of wrapping back to 1.0 when trying to zoom in or
out beyond the maximum factor.