Mark two new strings for translation.

Those strings weren't marked for extraction but we were trying to retrieve
their translation later.

At the same time, change the strings lookup context...
Remove the last remnant of the QObject translation context in
MythGallery and MythZoneMinder
MythArchive translation context change
Remove a redundant QObject:: prefix, the class ExportNative already inherit
it from QObject...

This changes the translation context as well...
Translation context change and new disambiguation strings.

Fix a typo in a translator comment of the ZoneMinder settings page
at the same time.
Replace a QObject::tr() that was missed
Remove a redundant QObject::, the class already inherits from QObject
Remove another redundant QObject::
Make translatable strings extractable and remove redundant QObject::
ChannelGroup translation context change
Miscellaneous translation fixes

Make some translatable strings extractable.

Add a new translatable string.

Change the translation context.
Translation context change
Another translation context change

We will get rid of those pesky QObject::tr()...
Merge branch 'master' of code.mythtv.org:mythtv