[libgda] (21 commits) ...Merge work on GdaData improvements

[Daniel Espinosa Ortiz <despinosa src gnome org>]

Summary of changes:

  8f5a4b5... GdaData: Added to_string() functons and items() to enums (*)
  a09196d... Allow compiling even with old Graphviz API (*)
  4e1dd55... JDBC provider: improved the way C pointers are passed throu (*)
  19a9aac... Memory leak correction (*)
  f78b049... [l10n] Updated Italian translation. (*)
  7d5bc5c... Fix GI annotations to Gdaui.DataSelector.get_selected_rows  (*)
  e509210... Misselaneos Unit Test improvements and for style (*)
  908b4e8... Moved DbTable.TableType.from_string () as a unum function m (*)
  38d7f04... Format corrections to Schema (*)
  f31aa3c... Added new GdaSqlExpression Class to allow GI to create GdaS (*)
  1b13ae7... Added GdaSqlSelect class to allow GI to create select expre (*)
  f011b59... Fixing API for GdaSqlExpression. Added to Makefile.am (*)
  88251ff... Added documentation to GdaSqlExpression methods. Removed Gd (*)
  61d4469... Added Since: clause to documentation (*)
  20af64b... GdaSqlExpression Last modifications. Saved just for future  (*)
  ecca91c... Removed GdaSqlExpression is not required due to GdaSqlBuild (*)
  b8960d8... Added equivalent() and compatible() methods to DbTable and  (*)
  4af4a15... Updated documentation for GdaData.DbTable and DbFieldInfo i (*)
  ae074ad... Fix typo on documentation. Added missing file to Makefile.a (*)
  7016c91... Fix libgda/Makefile.am by avoiding to delete VAPI and GIR f
  8a2df5f... Merge work on GdaData improvements

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