2.20.2 (stable):

* Backport the conversion to the new mm-common build infrastructure
  from the unstable branch.  This includes the installation of the
  shared mm-common documentation utilities, to ease the transition.
* Merged bugfixes from the unstable branch: #583657, #562810, #585027,
  #586785, #587766 (bugzilla.gnome.org)
* The recent gmmproc improvements from the development branch have
  also been merged, as well as a number of other minor corrections.