Updated the the example 'bitbake -h' output to match the actual
output, which has been recently patched to fix the
'-S SIGNATURE_HANDLER, --dump-signatures=SIGNATURE_HANDLER'
option.

Note also, that I have added a new option that has since appeared
in the output but was not in the manual's example.  That option
added is '--token=XMLRPCTOKEN'.

Reported-by: Richard Purdie <richard.purdie@linuxfoundation.org>
Signed-off-by: Scott Rifenbark <scott.m.rifenbark@intel.com>