Added a DispatcherWindow to dispatch ExecutableNodes.
Added a DispatcherWindow to dispatch ExecutableNodes.

Currently it can be launched using:
 - Menu /Execute/ExecuteSelected (Ctrl+E)
 - Execute Button in the Node Editor for any ExecutableNode
 - RMB on an ExecutableNode in the graph

chippey/gaffer,GafferHQ/gaffer,boberfly/gaffer,boberfly/gaffer,andrewkaufman/gaffer,ImageEngine/gaffer,appleseedhq/gaffer,goddardl/gaffer,johnhaddon/gaffer,appleseedhq/gaffer,lucienfostier/gaffer,cedriclaunay/gaffer,andrewkaufman/gaffer,andrewkaufman/gaffer,ivanimanishi/gaffer,andrewkaufman/gaffer,hradec/gaffer,hradec/gaffer,hradec/gaffer,cedriclaunay/gaffer,cedriclaunay/gaffer,appleseedhq/gaffer,johnhaddon/gaffer,boberfly/gaffer,cedriclaunay/gaffer,goddardl/gaffer,chippey/gaffer,goddardl/gaffer,lucienfostier/gaffer,GafferHQ/gaffer,ImageEngine/gaffer,johnhaddon/gaffer,hradec/gaffer,lucienfostier/gaffer,ivanimanishi/gaffer,ivanimanishi/gaffer,ivanimanishi/gaffer,ImageEngine/gaffer,GafferHQ/gaffer,GafferHQ/gaffer,ImageEngine/gaffer,GafferHQ/gaffer,goddardl/gaffer,chippey/gaffer,chippey/gaffer,andrewkaufman/gaffer,hradec/gaffer,appleseedhq/gaffer,johnhaddon/gaffer,johnhaddon/gaffer,lucienfostier/gaffer,boberfly/gaffer