RESOLVED - issue PROVA-91: Support nested Prova maps 
http://www.prova.ws/jira/browse/PROVA-91
RESOLVED - issue PROVA-91: Support nested Prova maps 
http://www.prova.ws/jira/browse/PROVA-91
RESOLVED - issue PROVA-91: Support nested Prova maps 
http://www.prova.ws/jira/browse/PROVA-91
RESOLVED - issue PROVA-93: The @vars annotation for joining on equal
variables in reaction groups can fail 
http://www.prova.ws/jira/browse/PROVA-93
RESOLVED - issue PROVA-92: Many tests do not clean up the Prova engines
they create 
http://www.prova.ws/jira/browse/PROVA-92
RESOLVED - issue PROVA-94: Provide shortened version for sending and
receiving messages  http://www.prova.ws/jira/browse/PROVA-94
RESOLVED - issue PROVA-95: Provide bracket-less syntax for Prova
relations  http://www.prova.ws/jira/browse/PROVA-95
Merge branch 'master' into sparql-plugin-optional