added more info about event triggers
added more info about event triggers

chrisdembia/simbody,scamille/simbody,elkingtonmcb/simbody,chrisdembia/simbody,elkingtonmcb/simbody,Gjacquenot/simbody,scamille/simbody,Gjacquenot/simbody,elen4/simbody,elkingtonmcb/simbody,robojukie/simbody,simbody/simbody,chrisdembia/simbody,Gjacquenot/simbody,simbody/simbody,elen4/simbody,scamille/simbody,robojukie/simbody,robojukie/simbody