Introduce ProcessFactory
Add WorkflowProcessor and related components

- Add ProcessFactory
- Add ProcessRepository
- Add prooph integration components
- Add first example scenario
- Provide basic test case set up
Merge pull request #35 from codeliner/workflow-processor

Workflow processor
Fix double checkMessageQueue call
Close #36: Handle Subprocess

- Child process now references parent TaskListPosition
- WorkflowProcessor handles StartChildProcess command
- WorkflowProcessor continues parent process if child is finished
Close #36: Handle failed child process
Merge pull request #43 from codeliner/subprocess

Subprocess
Seg fault debug commit
Rename TaskEntryChangedEvent::occur to TaskEntryChanged::at
Reactive failing test to see if seg fault is fixed
Refactor WorkflowEventRouter to SingleTargetMessageReouter

- The router now also routes command messages
- WorkflowMessageHandler was added to the list
  of allowed target handlers
Merge pull request #47 from codeliner/message-router

Refactor WorkflowEventRouter to SingleTargetMessageReouter