Fixed #14419 -- Enhanced the help text of the makemessages management command....

Fixed #14419 -- Enhanced the help text of the makemessages management command. Thanks lsaffre for the report and suggestions and gruszczy for the patch.
Also, removed the sterile make-messages.py, compile-messages.py scripts and dead compatibility code in makemessages.

git-svn-id: http://code.djangoproject.com/svn/django/trunk@15302 bcc190cf-cafb-0310-a4f2-bffc1f526a37