make yum_pkgs plugin executable standalone

plugins/yum_pkgs.py

@@ -227,3 +227,21 @@ class Backup(object):
         with open(self.output, 'wb') as f:
             f.write(self.pkglist)
         return()
+
+if __name__ == '__main__':
+    import argparse
+    args = argparse.ArgumentParser(description = 'Parse and report installed packages')
+    args.add_argument('-x', '--no-explicit',
+                      dest = 'explicit_only',
+                      action = 'store_false',
+                      help = ('If specified, catalogue ALL installed packages, '
+                              'not ones only explicitly-installed (implies -i/--includes)'))
+    args.add_argument('-i', '--includes',
+                     dest = 'include_deps',
+                     action = 'store_true',
+                     help = ('If specified, include packages installed as dependencies'))
+    args.add_argument('output',
+                      help = 'The file to write the XML output to.')
+    args = vars(args.parse_args())
+    b = Backup(**args)
+