[AppStream] AppStream 0.11.3 released!

[Matthias Klumpp]

This is a tiny bugfix release, but the changes are important enough to
warrant a release quickly after the previous one.

Tarballs available here: http://www.freedesktop.org/software/appstream/releases

Version 0.11.3
~~~~~~~~~~~~~~
Released: 2017-08-04

Bugfixes:
 * qt: Don't crash when an error is found and no error string is
passed (Aleix Pol)
 * Propagate document context to the context object for XML files
(Matthias Klumpp)
 * validator: Correctly recognize "launchable" as valid tag (Matthias Klumpp)

Translation:
 * Swedish
   - Anders Jonsson
 * Czech
   - Pavel Borecki
 * Catalan
   - Robert Antoni Buj Gelonch