Dropping FK before UK to avoid MySQL error 150

When I tryed to run the migration script I got error 150. 

To solve that I needed to remove ACT_FK_EXE_PROCDEF before ACT_UNIQ_RU_BUS_KEY.
Merge pull request #180 from spneto/patch-1

Dropping FK before UK to avoid MySQL error 150
ACT-1860: fix for postgres (wrong index name)
Merge branch 'master' of https://github.com/Activiti/Activiti
Added process-definition local listener declaration + tests
ACT-1860: fix for DB2
Merge branch 'master' of https://github.com/Activiti/Activiti
Using bpmn20.xml as extension, for some reason git ignores the bpmn-file
Merge remote-tracking branch 'upstream/master'