Fix pylint warnings in cli/acl.py.

This CL has the side effect of ensuring that the autotest ebuilds are uprevved,
which is needed for fixing some breakage associated with corrupted prebuilts.

BUG=none
TEST=pylint passes.

Change-Id: If8119ae9080e0ed4462356bd73587dc161bcc885
Reviewed-on: https://gerrit.chromium.org/gerrit/43856
Commit-Queue: David James <davidjames@chromium.org>
Tested-by: David James <davidjames@chromium.org>
Reviewed-by: Brian Harring <ferringb@chromium.org>

cli/acl.py

diff --git a/cli/acl.py b/cli/acl.py
index 0b20acf..708bd63 100644
--- a/cli/acl.py
+++ b/cli/acl.py
@@ -17,7 +17,6 @@
 
 """
 
-import os, sys
 from autotest_lib.cli import topic_common, action_common
 
 
@@ -45,6 +44,7 @@
 
 
     def get_items(self):
+        """Get the items in the ACL list."""
         return self.acls
 
 
@@ -168,6 +168,8 @@
 
 
 class acl_add_or_remove(acl):
+    """Shared implementation for acl add and acl remove."""
+
     def __init__(self):
         super(acl_add_or_remove, self).__init__()
         # Get the appropriate help for adding or removing.