Fix upgrade scripts for column TASK_FORM_KEY_ in ACT_RU_TASK
Merge pull request #323 from henryyan/db_form-key

Fix upgrade scripts for column TASK_FORM_KEY_ in ACT_RU_TASK
Job executor refactoring + reuse command context when possible
Merge branch 'master' of https://github.com/Activiti/Activiti
Make job query the same for all databases (including mysql)
Fixed MySQL test issue
Fixed MSSQL table script issue
autoincrement added back to mssql script