Enqueue episodes in Totem also (bug 1775)

Thanks to Eric Le Lay for the patch
Gtk UI: Fix submenu activation/focus issues (bug 1778)

This fixes the same problem as outlined in bug 1778, but also
makes sure that keyboard navigation still works.
Extensions: Cleaned up "Enqueue in Media Player"
Remove "print" statement in enqueue_in_mediaplayer
Gtk UI: Show notification bubbles when downloads fail (bug 1265)

Don't show the GTK message dialog when downloads fail.
Just show the pyNotify message dialog.
Tools: Ubuntu PPA generator for "raring" release
Gtk UI: Clear filter using secondary icon in GtkEntry

Requires Gtk+ >= 2.16, which has been released in March 2009.
The corresponding PyGtk 2.16 release was in August 2009.
Makefile: Build ".pyo" files on "make install" (bug 1786)
Database: Check if every episode is assigned to a podcast
Model: Disallow subscribing to an already-existing URL
QML UI: Directly add a podcast via feed URL

Don't go through gpodder.net if the user enters a URL
directly into the search field. This also fixes various
bugs / annoyances related to adding/removing podcasts in
the QML UI (e.g. updating "All episodes" counts).
Windows: Mandatory notification extension (pull request 72)
Device sync: Sanitized playlist filename (bug 1788)
Device sync: Sanitize mount point encoding (bug 1785)
Extensions: Merge audio/video converter extensions (bug 1783)

There were similar extensions which have been folded into one:

 - 2 similar audio extensions -> the audio_converter extension
 - 2 similar video extensions -> the video_converter extension

With this change it's now possible to change the video output format in
the advanced settings to mp4 (default) or avi.
QML UI: Reset selection when episode list changes (bug 1804)

This avoids having an item selected when deleting episodes or when
some other event changes the list of episodes.
QML UI: Make selection background color visible again
QML UI: Convert selection indices to integers (bug 1802)

This fixes a bug where multi-selection episode actions don't
work in recent versions.
CLI: Fix subscribe/unsubscribe when list has not been loaded yet
QML UI: Highlight podcasts on Harmattan, but not on Sailfish

From user feedback, the colored text highlight in the podcast list
for podcasts with new episodes has been received better than the
new "triangle" indicator. So we'll now show the colow highlights on
Harmattan (with black background), whereas on Sailfish we still
don't show it (at least with the default background in the emulator,
the white text looks better than the colored text).