[gtkmm] (5 commits) Non-fast-forward update to branch wip/dboles/filefilter-docs

[Daniel Boles <dboles src gnome org>]

The branch 'wip/dboles/filefilter-docs' was changed in a way that was not a fast-forward update.
NOTE: This may cause problems for people pulling from the branch. For more information,
please see:

 https://wiki.gnome.org/Git/Help/NonFastForward

Commits removed from the branch:

  2283f40... FileFilter: Format docs copied in from GTK better
  e5059d2... FileFilter: Fix no documentation of custom rules
  aaffe11... FileFilter: Don’t mention unwrapped func .filter()

Commits added to the branch:

  41d1b57... tools/gen_scripts: Update for non-source-dir builds (*)
  f92a9ba... FileFilter: Format docs copied in from GTK better
  edd1b12... FileFilter: Fix no documentation of custom rules
  6b4ea72... FileFilter: Don’t mention unwrapped func .filter()
  bff474a... FileFilter: Remove commented-out _WRAP_METHOD call

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