Added support for domain models into draggables.
- DraggableJPanel now takes a generic type and includes a domainModel
  parameter to its constructor of that generic type.
- SequenceStart refactored to follow pattern (reference implementation)
- EditorCanvas retrieves domain model of draggable if it's a SequenceStart
  upon add of draggable.
Updated SequenceVariable to follow additions to DraggableJPanel.
Updated SequenceEvent to cohere to changes in DraggableJPanel.
Updated SequenceAction to cohere to changes to DraggableJPanel.
Updated DraggableCondition to cohere to changes in DraggableJPanel.
Implemented reference implementation for a sequence action.
- AbstractConfigurable to provide domain objects with parameters.
- Actionable to provide an interface for performing behavior.
- SequenceAction to provide an annotation for marking modular classes as
  SequenceActions.
- SimpleLogAction ( sequence action reference implementation)
Sample SimpleLogAction working from discovery to visualization.
STILL NEEDED: Working from discovery to execution
Cleaning up imports.
Added potential Tracing capability class.