[vala] (4 commits) Non-fast-forward update to branch staging

[Rico Tzschichholz <ricotz src gnome org>]

The branch 'staging' 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:

  f00ab1c... vala: Warn about unsupported cast to void and drop it
  b713f09... valadoc: Correctly format background of inline @link's

Commits added to the branch:

  8ac0970... vala: Warn about unsupported cast to void and drop it (*)
  17a8486... tests: Add missing cast-void-not-allowed.c-expected (*)
  8b894d6... valadoc: Correctly format background of inline @link's (*)
  37db812... vala: Don't restrict element type of GLib.Array

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