[AppStream] AppStreamGlib 0.6.6

[Richard Hughes]

Version 0.6.6
~~~~~~~~~~~~~
Released: 2016-12-15

New Features:
 - Add a refcounted overloaded C string object and use in most objects
(Richard Hughes)
 - Add AS_APP_QUIRK_IS_PROXY (Richard Hughes)
 - Add as_release_state_to_string() (Richard Hughes)
 - Add Geary to the app id fallbacks (Niels De Graef)
 - Add support for ONLY_NATIVE_LANGS when parsing yaml files (Richard Hughes)

Bugfixes:
 - Deduplicate the AsNode attribute key and value using a hash table
(Richard Hughes)
 - Detect invalid files in the libyaml read handler (Richard Hughes)
 - Do not absorb core addons into the main application (Richard Hughes)
 - Do not add <kudos>, <languages>, <provides> or <releases> for
addons (Richard Hughes)
 - Do not save the attributes if the node or parent node is ignored
(Richard Hughes)
 - Lazy load more structures in libappstream-glib (Richard Hughes)
 - Set a better icon for codecs (Kalev Lember)

Richard.