Italian translation uodate from Morris Cavestro

New MythArchive, MythBrowser, MythNetvision and MythZoneMinder
translations.

Updated MythGallery, MythMusic, MythNews and MythWeather translation.

Thank you Morris!

Closes #10912

Signed-off-by: Nicolas Riendeau <nriendeau@mythtv.org>
Allow interlaced video to play using VDA when using Mountain Lion

Apple has fixed (some) issues with VDA in Mountain Lion. Interlaced videos that used to cause a kernel panic now either play properly, or the decoder returns an error and so the code default to software decoder
Add general methods for emitting and retrieving TV playback status via Qt signals.

Those methods will be used in order to retrieve TV playback status in a synchronous fashion by AirPlay.
Ultimately, all current status events should have their signals equivalent

Make distclean && configure is required
Emit appropriate signals indicating playback status.

Signals currently emitted are:
- TVPlaybackAborted: TV playback failed to start (typically, TV playback was started when another playback is currently going)
- TVPlaybackStarted: TV playback has started, video is now playing
- TVPlaybackStopped: TV playback has stopped and playback has exited
- TVPlaybackUnpaused: TV playback has resumed, following a Pause action
- TVPlaybackPaused: TV playback has been paused
- TVPlaybackSought(qint position_seconds): Absolute seek has completed

Also add IsPaused utility (static). Will return true is playback is currently ongoing.
Allows multiple sessions to Airplay and RAOP

This is done by stopping the one currently running or stopping any current playback.

This change allows to always be able to start airplay and not silently fail should a playback be currently going. If a current playback is currently going (either RAOP, AirPlay or standard playback), it will be stopped and a new session will be automatically started.
AirPlay now waits synchronously for any events to be completed: this result in much smoother user interaction and also follow Apple's user experience guidelines with their MFi vendors.

A side effect is that since iOS 5.1, a typical AirPlay session would open both a RAOP session and an AirPlay one, to drop the RAOP connection a few seconds later. This caused the audio card to be already in use for AirPlay and resulted in no audio during playback

There is an issue with iOS devices when using RAOP, they don't detect that the connection got interrupted and continue sending data. iTunes behaves properly.

Fixes #10885
Fix build warnings about modifying a const variable
'none' is not a valid URL and ignoring it just masks bugs elsewhere in the code
Add a weather grabber using the official MetOffice API for the UK

This will probably replace the broken BBC grabbers.

This is still a work in progress. Currently offers 6 (just 5 available) and 3
day screens. An 18 hour and possibly a new 24 hour screen will be
added soon. A current observations grabber is also planned but a lower
priority for now.

Search doesn't include any caching yet, but the plan is to have it
fully cached.

Please report bugs to the mailing list.
MythGame miscellaneous translations files (context, etc...)
Merge branch 'master' of code.mythtv.org:mythtv
MythNews small context change
Small MythWeather translation context change
Make translatable dish tv categories

Make translatable dish tv categories and put them in a new
translation context into which other tv categories will be
transferred later.
Add MythCoreContext::WaitUntilSignals convenience method.

This will simplify the definition and use of Qt signals.
Use MythCoreContext::WaitUntilSignals and fix pausing while playback is running
Don't store the last used DVD device

This prevents users with multiple drives from using the second one at
a later time. There's no good reason to force the use of only one drive.
Only prompt the user to select from 'usable' media

If a user has multiple optical drives but only one or two contain discs
then there is no need to show all in the drive selection popup. In
cases where only one drive contains media this avoids showing the popup at all.
Fix 'cancel' option when selecting DVD device
Updated Greek MythFrontend, MythGallery, MythGame, MythMusic,
MythNews and MythWeather translation from Yianni Vidalis

Thank you Yianni!

Closes #10913

PS: I'll be sending you a list of entries that were confirmed empty
in MythFrontend which should be filled in.

Signed-off-by: Nicolas Riendeau <nriendeau@mythtv.org>
Add playback registration handling

It is an unfortunate fact that you can only do one playback at a time within a frontend; usually because you can only open one audio session at a time.
This commit provides a mechanism for playback objects (such as TV, AirPlay, RAOP, MythMusic) to register themselves as a player and request playback; in which case all other registered player will be asked to close.