Dummy merge: Mark 2.2-stable as merged into default up to point of migration

Development in the Mercurial repository started after b291c29ca994 (for
default) and 82733a4020a0 (for 2.2-stable). There are still some changesets
in the 2.2-stable branch that need to be ported to default, this can be
determined by comparing release-notes.txt.