[tracker-miners] (14 commits) ...Merge branch 'wip/carlosg/writeback-refactor' into 'master'

[Sam Thursfield <sthursfield src gnome org>]

Summary of changes:

  2a175cb... tracker-writeback: Add hooks for new writeback functions (*)
  9ca9cc5... writeback: Port playlist module to new API (*)
  454b01e... writeback: Port XMP writeback module to new API (*)
  cc9627a... writeback: Port gstreamer module to new API (*)
  21b2b70... tracker-writeback: Move TrackerWritebackFile to write_metad (*)
  f52e94a... tracker-writeback: Drop implicit/explicit task cancellation (*)
  401f853... tracker-writeback: Drop GetPid DBus call (*)
  8ca6fa2... tracker-writeback: Change Writeback() DBus API (*)
  956f7a1... tracker-writeback: Drop internal TrackerSparqlConnection (*)
  3a0aa24... tracker-miner-fs: Drop tracker-writeback interaction (*)
  642a6bc... data: Drop enable-writeback gsettings key (*)
  4bc5e0e... tests: Restore writeback-audio and writeback-images functio (*)
  f37bd39... tests: Drop writeback-image-details functional test (*)
  d04f98a... Merge branch 'wip/carlosg/writeback-refactor' into 'master'

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