This adds space-tool and lasso-tool as required modules to the BPMN
palette. That in term ensures that users can simply reuse the palette
without further configuration.
This commit adds the ability to model participants from the palette.
* Empty diagrams can be used as a start for participant _AND_ process diagram
* Process diagrams can be converted to collaboration diagrams by dropping
a participant onto them
Closes#128
pedesen
Nico Rehwaldt
Ricardo Matias
Nico Rehwaldt
jdotzki