Fix some appstream XML validation errors/warning.

[ajf8]

I didn't get the message about the description being too short reported in issue #37

But there were some others which this hopefully fixes:

 appstreamcli validate data/transmission-remote-gtk.appdata.xml.in --verbose --pedantic
W - transmission-remote-gtk.appdata.xml.in:transmission-remote-gtk.desktop:19
    Found tag '_li' in section 'ul'. Only 'li' tags are allowed.

W - transmission-remote-gtk.appdata.xml.in:transmission-remote-gtk.desktop:10
    Found invalid tag: '_developer_name'. Non-standard tags must be prefixed with 
    "x-".

E - transmission-remote-gtk.appdata.xml.in:transmission-remote-gtk.desktop
    The component is missing a long description. Components of this type must have a 
    long description.

W - transmission-remote-gtk.appdata.xml.in:transmission-remote-gtk.desktop:18
    Found tag '_p' in 'description' section. Only 'p', 'ul' and 'ol' are allowed.

W - transmission-remote-gtk.appdata.xml.in:transmission-remote-gtk.desktop:15
    Found tag '_p' in 'description' section. Only 'p', 'ul' and 'ol' are allowed.

W - transmission-remote-gtk.appdata.xml.in:transmission-remote-gtk.desktop:4
    The component ID is not a reverse domain-name. Please update the ID and that of 
    the accompanying .desktop file to follow the latest version of the Desktop-Entry 
    and AppStream specifications and avoid future issues.

P - transmission-remote-gtk.appdata.xml.in:transmission-remote-gtk.desktop:4
    The component is part of the GNOME project, but its id does not start with 
    GNOMEs reverse-DNS name ("org.gnome").

Validation failed: errors: 1, warnings: 5, pedantic: 1

[TingPing]

Why are you disabling translations?

EDIT: What i mean is, don't run the appstream tool on the .in file, run it on the output.

[TingPing]

You have to actually rename the desktop file too of course.

[ajf8]

Hopefully fixed, thanks.