CmdlineError should exit with a 1

Tools like livemedia-creator need to know that the exit was due to an
error so call sys.exit with a 1.

Related: rhbz#1102318

(cherry picked from commit a9b4e05)

Related: rhbz#1196721

pyanaconda/exception.py

@@ -145,7 +145,7 @@ def handleException(self, dump_info):
                         # for a few seconds before exiting the installer
                         print(cmdline_error_msg)
                         time.sleep(10)
-                        sys.exit(0)
+                        sys.exit(1)
                     else:
                         print("\nAn unknown error has occured, look at the "
                                "/tmp/anaconda-tb* file(s) for more details")