Improve the help text for 'repo upload'

Signed-off-by: Shawn O. Pearce <sop@google.com>
diff --git a/subcmds/upload.py b/subcmds/upload.py
index de3fe85..24bbc7b 100644
--- a/subcmds/upload.py
+++ b/subcmds/upload.py
@@ -38,22 +38,21 @@
 %prog [--re --cc] {[<project>]... | --replace <project>}
 """
   helpDescription = """
-The '%prog' command is used to send changes to the Gerrit code
-review system.  It searches for changes in local projects that do
-not yet exist in the corresponding remote repository.  If multiple
-changes are found, '%prog' opens an editor to allow the
-user to choose which change to upload.  After a successful upload,
-repo prints the URL for the change in the Gerrit code review system.
+The '%prog' command is used to send changes to the Gerrit Code
+Review system.  It searches for topic branches in local projects
+that have not yet been published for review.  If multiple topic
+branches are found, '%prog' opens an editor to allow the user to
+select which branches to upload.
 
-'%prog' searches for uploadable changes in all projects listed
-at the command line.  Projects can be specified either by name, or
-by a relative or absolute path to the project's local directory. If
-no projects are specified, '%prog' will search for uploadable
-changes in all projects listed in the manifest.
+'%prog' searches for uploadable changes in all projects listed at
+the command line.  Projects can be specified either by name, or by
+a relative or absolute path to the project's local directory. If no
+projects are specified, '%prog' will search for uploadable changes
+in all projects listed in the manifest.
 
 If the --reviewers or --cc options are passed, those emails are
 added to the respective list of users, and emails are sent to any
-new users.  Users passed to --reviewers must be already registered
+new users.  Users passed as --reviewers must already be registered
 with the code review system, or the upload will fail.
 
 If the --replace option is passed the user can designate which
@@ -83,6 +82,11 @@
   [review "http://review.example.com/"]
     autoupload = true
 
+References
+----------
+
+Gerrit Code Review:  http://code.google.com/p/gerrit/
+
 """
 
   def _Options(self, p):