moved to base class for shell plugins

fish now sets env vars correctly
fish checksum now works
fixed and cleaned up imports
fixed typo

lib/ansible/plugins/shell/powershell.py

@@ -20,9 +20,7 @@ __metaclass__ = type
 import base64
 import os
 import re
-import random
 import shlex
-import time
 
 from ansible.utils.unicode import to_bytes, to_unicode