Re-applying lost commit from 5.7-alf for altering column-size
Allow setting the TransactionSychrinizationAdapter order for failed job
ACT-1731: Fixed issue with byteArray initialisation in joined-queries
ACT-1731: Binary variables fetched with task now get loaded in-context
Corrected URL in REST-docs
ACT-1649: Deadlock occured in load test with db2

Added indexes to DB2. Also added some missing indexes to MSSQL
Merge branch 'master' of github.com:Activiti/Activiti
ACT-1649: no upgrade, but added notes in read me