Use millisecond precision for timestamps in mysql
First modification for recovering workflow instances from dead executors:
1) Rename owner->executorGroup
2) Create new nflow_executor table
3) Allocate new executorId when starting by inserting to nflow_executor
4) replace is_running with executor_id
5) fix dao unit test database initialization sequence
Recover workflow executors that have been marked runnable by executors that have not been active in last 15 minutes
Register official JodaModule to nflow-ObjectMapper in engine
Clone nflow-ObjectMapper into nflow-rest-ObjectMapper and actually use it in nflow-jetty
Return executionStartTime and -EndTime to ISO-8601 format instead of milliseconds
Added integration test for workflow action history
Actually removed custom JacksonJodaModule and used JodaModule in nflow-tests
Make sure WorkflowDispatchers wakes up often enough to keep the database keepalive stamp moving even if workflows are progressing slowly
Detect legact mysql versions and use separate ddl for them
Set current_timestamp instead of current_time when calculating mysql currentTimePlusSeconds
Notify travis-ci build status to flowdock
Merge pull request #7 from NitorCreations/recover_workflows

Recover workflow instances from dead executors