[gtk] (14 commits) ...Merge branch 'matthiasc/for-master' into 'master'

[Matthias Clasen <matthiasc src gnome org>]

Summary of changes:

  51d3575... Cosmetics (*)
  29ccd13... docs: Stop referring to the Quartz backend (*)
  3617fba... docs: Include GDK_WINDOWING_MACOS (*)
  574a3a4... gdk: Drop GdkPoint from the api (*)
  1f8d593... docs: Add some detail to GdkTexture docs (*)
  838d092... docs: Tweak GdkPaintable docs (*)
  9f71bdd... docs: Cosmetics (*)
  2df3822... docs: Small additions for GdkCursor docs (*)
  d2adbad... docs: Tweak frame clock docs (*)
  3afd5d7... docs: Tweak GdkSurface docs (*)
  94305f2... docs: Tweak GdkPopup docs (*)
  ce78d0c... docs: Tweak GdkToplevel docs (*)
  3164f32... docs: Some restructuring (*)
  5a77994... Merge branch 'matthiasc/for-master' into 'master'

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