Fix missing imports from sysctl module

This module was missing an import of get_exception()
and had an unused import of 're'

lib/ansible/modules/system/sysctl.py

@@ -117,8 +117,8 @@ EXAMPLES = '''
 
 import os
 import tempfile
-import re
-from ansible.module_utils.basic import get_platform, AnsibleModule, BOOLEANS_TRUE, BOOLEANS_FALSE
+from ansible.module_utils.basic import get_platform, get_exception, AnsibleModule, BOOLEANS_TRUE, BOOLEANS_FALSE
+
 
 class SysctlModule(object):