[libgee] (15 commits) Non-fast-forward update to branch wip/issue/23

[Rico Tzschichholz <ricotz src gnome org>]

The branch 'wip/issue/23' 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:

  36e8e07... Keep the original exception in Future.map/flat_map

Commits added to the branch:

  35226d9... Guard GLib.Cond.wait/wait_until calls against spurious or s (*)
  2b646cc... Flatten call structure a bit (*)
  56b10bc... Release 0.20.3 (*)
  8b76b8c... Various English and typo fixes in the documentation (*)
  63d2b88... Replace Memory.dup() with GLib.malloc() and Memory.copy() (*)
  2ba2faf... Remove invalid usage of type-argument for Gee.Future.Source (*)
  db2efd4... Release 0.20.4 (*)
  f0ccfe9... Add more missing generic type arguments (*)
  7f93f22... gee/Makefile.am: include Makefile.introspection (*)
  ebf7691... Add more missing generic type arguments (*)
  ab19a43... Release 0.20.5 (*)
  4ed45f6... Various English and typo fixes in the documentation (*)
  b85a10c... Add more missing generic type arguments (*)
  6cc0994...  doap: Demote idle maintainers to authors (*)
  abcf0b3... Keep the original exception in Future.map/flat_map

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