g-ir-scanner includes section docs as class/interface docs if the section name is equal to the lowercase type name.
Since all the documentation is in section blocks, rename them to match the type names.
https://bugzilla.gnome.org/show_bug.cgi?id=727776
+ Make the pspec_hash function an internal util.
+ Add a create_props_hashtable implementation
+ If TRACK_TYPE_AUDIO, put the volume properties in the hashtable.