make sure that options are quoted, as people can add a shell

script there with a comma that would produce invalid configuration
upon being wrote again

library/system/authorized_key

@@ -256,7 +256,7 @@ def writekeys(module, filename, keys):
                     option_strings = []
                     for option_key in sorted(options.keys()):
                         if options[option_key]:
-                            option_strings.append("%s=%s" % (option_key, options[option_key]))
+                            option_strings.append("%s=\"%s\"" % (option_key, options[option_key]))
                         else:
                             option_strings.append("%s " % option_key)