broken sxd file for signatures workflow. Added dumb certificates creator shell script for testing purposes in qa. Change-Id: Ibee17193a1a38348f2e7fc460dfdd0c54dd31f9b Reviewed-on: https://gerrit.libreoffice.org/c/core/+/155932 Tested-by: Jenkins Reviewed-by: Thorsten Behrens <thorsten.behrens@allotropia.de> 
Updated the README Documentation file for xmlsecurity module. Fixed
broken sxd file for signatures workflow. Added dumb certificates creator
shell script for testing purposes in qa.

Change-Id: Ibee17193a1a38348f2e7fc460dfdd0c54dd31f9b
Reviewed-on: https://gerrit.libreoffice.org/c/core/+/155932
Tested-by: Jenkins
Reviewed-by: Thorsten Behrens <thorsten.behrens@allotropia.de>