[vala] (10 commits) Non-fast-forward update to branch wip/gio-2.0

[Rico Tzschichholz <ricotz src gnome org>]

The branch 'wip/gio-2.0' 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:

  0a17066... gio-2.0: Fix binding of Resolver.lookup_service*()

Commits added to the branch:

  33879ec... Check for assignment to constant (*)
  c87fb97... vapi: Add PolicyKit bindings, polkit-agent-1 and polkit-gob (*)
  c4f405b... vapi: Update GIR-based bindings (*)
  aca65c5... Release 0.34.0 (*)
  4094b05... glib-2.0: Allow null as argmument for string.escape() (*)
  57441df... Add support for the \v escape charactor (*)
  63fa61b... webkit2gtk: URI*.get_http_headers returns unowned Soup.Mess (*)
  5c9b22e... glib-2.0: Update Unicode symbols (*)
  0707a56... gio-2.0: Fix binding of Resolver.lookup_service*()
  27d1fcd... gio-2.0: Keep GLib.Socket API compatible with gio < 2.48

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