Appdata files for gobby/gobby05

Bugs filed on Fedora RHBZ:
https://bugzilla.redhat.com/show_bug.cgi?id=1025924
https://bugzilla.redhat.com/show_bug.cgi?id=1025923
Merge pull request #14 from sanjayankur31/appstream-additions

Appdata files for gobby/gobby05
Rename the gobby AppData file to reflect the name of the desktop file
Add screenshots for geany
Add screenshots for gnome-tweak-tool
Add screenshots for wireshark