[tracker] (42 commits) ...Merge branch 'wip/carlosg/serialize-api' into 'master'

[Sam Thursfield <sthursfield src gnome org>]

Summary of changes:

  cb716cd... libtracker-data: Plug leak (*)
  e62f328... libtracker-data: Plug string leak (*)
  6d298c9... libtracker-data: Convert blank nodes in DESCRIBE queries (*)
  5a50f5f... libtracker-data: Add missed GTypes in conversion (*)
  787c4ff... libtracker-sparql: Ensure to register a single instance of  (*)
  85f58be... libtracker-sparql: Add internal Turtle format TrackerSerial (*)
  799f4b3... libtracker-sparql: Add tracker_sparql_connection_serialize_ (*)
  fbca0ab... libtracker-data: Add internal API to tell whether a query m (*)
  98a5ae8... libtracker-sparql: Implement serialize_async/finish in dire (*)
  89e9a4f... libtracker-data: Use SQL value type as a last resort to det (*)
  bb2665a... libtracker-sparql: Fix refcount management of a serializer' (*)
  9e13947... libtracker-data: Provide graph information at describe quer (*)
  f57943e... libtracker-sparql: Support serialization to Trig format (*)
  39b365a... libtracker-sparql: Implement serialize_async/finish on DBus (*)
  883bc6f... libtracker-sparql: Implement serialize_async/finish on remo (*)
  68d894e... cli: Use serialize() method for "tracker3 export" command (*)
  7c721e2... libtracker-data: Hint best tracker_triples access strategy  (*)
  d2c427c... libtracker-sparql: Add TrackerSparqlStatement API to serial (*)
  c2269b5... libtracker-sparql: Implement serialization on direct statem (*)
  6c9b95e... libtracker-sparql: Handle statement serialization in D-Bus  (*)
  33b2d51... libtracker-sparql: Implement statement serialization in D-B (*)
  c20fd77... libtracker-sparql: Add missing "static" in functions (*)
  84d3931... libtracker-sparql: Implement statement serialization on rem (*)
  f42768b... tests: Add serialize tests (*)
  3387e76... libtracker-sparql: Fix typo (*)
  bb1f896... docs: Add documentation blurb about DESCRIBE resultset form (*)
  15534e0... libtracker-data: Do not forward cursor variable names separ (*)
  a760bd1... libtracker-data: Add n_columns argument to cursors (*)
  d6edfe3... libtracker-data: Store the number of columns in select cont (*)
  9df641d... libtracker-data: Forward number of columns to cursor (*)
  1259052... libtracker-data: Handle annotating value types in cursors (*)
  3b6b03e... libtracker-data: Refactor code (*)
  2d53fec... libtracker-data: Forward annotated column types on SELECT q (*)
  99bfe6c... libtracker-data: Forward annotated column type on ASK queri (*)
  3d0af50... libtracker-data: Forward annotated column types on DESCRIBE (*)
  9bb85f7... libtracker-data: Do not forward static value types to curso (*)
  ef83e7c... libtracker-data: Skip nrl:added/nrl:modified while parsing  (*)
  a23eb55... libtracker-data: Add missing locking to cursor API (*)
  47598d5... docs: Document how the annotated types in cursors affect li (*)
  dab5b71... libtracker-sparql: Add TrackerSerializeFlags argument to se (*)
  c63f9e6... libtracker-data: Return NULL on failed date conversions (*)
  54119de... Merge branch 'wip/carlosg/serialize-api' into 'master'

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