Unify style of subcommand docstrings in git-cl

Review URL: https://codereview.chromium.org/1057883003

git-svn-id: svn://svn.chromium.org/chrome/trunk/tools/depot_tools@294665 0039d316-1c4b-4281-b951-d872f2087c98

git_cl.py

@@ -2897,7 +2897,7 @@ def CMDset_close(parser, args):
 
 
 def CMDdiff(parser, args):
-  """shows differences between local tree and last upload."""
+  """Shows differences between local tree and last upload."""
   parser.parse_args(args)
   cl = Changelist()
   issue = cl.GetIssue()
@@ -2926,7 +2926,7 @@ def CMDdiff(parser, args):
 
 
 def CMDowners(parser, args):
-  """interactively find the owners for reviewing"""
+  """Interactively find the owners for reviewing."""
   parser.add_option(
       '--no-color',
       action='store_true',