Add feature so that properties of the form
common.toolid.launch=String
Act as if they came from the LTI Proxy Tool Registration file with
"final" set to true. If these are set in the sakai.properties *and*
in the tool registation, the sakai.properties - wins.
For example:
sakai.simplelti.launch=http://simplelti.appspot.com/launch
sakai.simplelti.password=secret
When the IMS SimpleLTI tool is multiply registered, each common tool id
can do this separately.