Respect results of WOA.
[AE/CA] Only restore the default format if we ask for it.
[AE/CA] Simplify the ResetAudioDevices code and make sure it actually works

The old code failed to reset devices set in Encoded mode and it was
going about it in a fashion that duplicated a lot of code. This removes
all the custom code and uses already exisisting functions and that
actually makes the code functional.
linux: allow root user to raise priority
[airtunes] - fix - show metadata/coverart on first song aswell by delaying the update to the "OnPlay" event. (before we wouldn't set metadata/coverart because we get it before playback in our player really starts).
[spectrum] Avoid zero height bars that cause display artefacts
[texture] - if FreeResources is called with "immediately" flag set - ensure that this texture is really invalidated - and don't deliver it on the next load from unused texture list
[gui] - don't eat messages in GUIWindowHome but pass them to the base impl.
Merge pull request #3840 from FernetMenta/linux

linux: allow root user to raise priority
videodb: don't show user credentials in source unavailable prompt during library cleaning
Merge pull request #3848 from Memphiz/airtunesanticache

[AirTunes] - fix coverart
Merge pull request #3845 from popcornmix/spectrum_depth

[spectrum] Avoid zero height bars that cause display artefacts
[cosmetics] - fixed typo - sucess* -> success*
Merge pull request #3617 from t-nelson/respect_woa

Respect results of WOA.
Merge pull request #3818 from Memphiz/osxresetaudio

[osx/ae/ca] - fix ResetAudioDevices
Merge pull request #11 from xbmc/master

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