[tracker] (13 commits) ...Merge branch 'gstreamer-with-dlna'

[Martyn James Russell <mr src gnome org>]

Summary of changes:

  6db93bb... tracker-extract: disable compilation of the gupnp-dlna extr (*)
  fdfe64e... tracker-extract: let gstreamer extractor handle 'dlna/*' mi (*)
  3eb6b1c... build: explictly require gstreamer when building gupnp-dlna (*)
  cac33fa... build: new --with-gstreamer-backend=[tagreadbin,decodebin2, (*)
  7350423... build: rename --enable-video-extractor to --enable-generic- (*)
  10df222... build: minor spaces vs tabs fixes (*)
  56aac39... tracker-extract,gstreamer: don't compile both tagreadbin an (*)
  bc646e3... tracker-extract,gstreamer: integrate GUPnP-DLNA extractor w (*)
  ec7a70a... build: treat GUPnP-DLNA as another GStreamer backend (*)
  ea036f9... tracker-extract,gstreamer: avoid code duplication (*)
  7fa1e12... build: require gstreamer-pbutils when using Discoverer back (*)
  4028a7a... tracker-extract: Small coding style clean ups (*)
  3728fb6... Merge branch 'gstreamer-with-dlna'

(*) This commit already existed in another branch; no separate mail sent