Appdata file for gwibber

Just the one file.

Submitted to fedora bugzilla:
https://bugzilla.redhat.com/show_bug.cgi?id=1026133

Filed upstream:
https://bugs.launchpad.net/gwibber/+bug/1247704
Modify hotot appdata file

The desktop file in hotot-gtk is hotot.desktop, not hotot-gtk.desktop as
the older file listed.

$ rpm -ql hotot-gtk | egrep desktop
/usr/share/applications/hotot.desktop
Modify hotot desktop file and add one for hotot-qt

Modified the summary so folks can see the different frontends.
Merge pull request #15 from sanjayankur31/appstream-additions

Appdata file for gwibber + hotot