Added hyphen-only options

Some options have words separated by underscores. Added options with
same name and underscores replaced by hyphens.

BUG=400953

Review URL: https://codereview.chromium.org/436963005

git-svn-id: svn://svn.chromium.org/chrome/trunk/tools/depot_tools@288366 0039d316-1c4b-4281-b951-d872f2087c98
diff --git a/git_cl.py b/git_cl.py
index 77f4a9e..acc6830 100755
--- a/git_cl.py
+++ b/git_cl.py
@@ -1718,7 +1718,9 @@
                     help='cc email addresses')
   parser.add_option('-s', '--send-mail', action='store_true',
                     help='send email to reviewer immediately')
-  parser.add_option("--emulate_svn_auto_props", action="store_true",
+  parser.add_option('--emulate_svn_auto_props',
+                    '--emulate-svn-auto-props',
+                    action="store_true",
                     dest="emulate_svn_auto_props",
                     help="Emulate Subversion's auto properties feature.")
   parser.add_option('-c', '--use-commit-queue', action='store_true',
@@ -1726,6 +1728,7 @@
   parser.add_option('--private', action='store_true',
                     help='set the review private (rietveld only)')
   parser.add_option('--target_branch',
+                    '--target-branch',
                     help='When uploading to gerrit, remote branch to '
                          'use for CL.  Default: master')
   parser.add_option('--email', default=None,