appdata: Improve appdata for AppStream 1.0

- Add appstreamcli support to validate the appdata file.
- Add missing release information.
- Use the `<developer><name>` tag instead of the deprecated `<developer_name>`

data/meson.build

@@ -8,13 +8,24 @@ if get_option('gtk') and get_option('libsysprof')
            output: 'org.gnome.Sysprof.appdata.xml.in',
     configuration: config_h,
   )
-  i18n.merge_file(
+  appdata_file = i18n.merge_file(
             input: appdata_in,
            output: '@0@.appdata.xml'.format(app_id),
            po_dir: podir,
           install: true,
       install_dir: join_paths(datadir, 'metainfo')
   )
+  # Validate Appdata
+  appstreamcli = find_program('appstreamcli', required: false)
+  if appstreamcli.found()
+    test(
+      'validate-appdata', appstreamcli,
+      args: [
+        'validate', '--no-net', '--explain', appdata_file
+      ],
+      depends: appdata_file,
+    )
+  endif
 
   desktop_in = configure_file(
             input: 'org.gnome.Sysprof.desktop.in.in',