activation setter/getter for gates,

targetting the `default` sheaf
PsiDispatcher CleanUp and smpmap2 Hack removed.
Merge branch 'master' of https://github.com/joschabach/micropsi2
implemented a working ground type minecraft experiment
introduce datatarget_feedback

worldadapters and actors now support datatarget_feedback to communicate the outcome of an action back to the nodenet.
actors will read the feedback values within their nodefunctions, the worldadapter should set them when the world is stepped
edited minecraft readme with working ground type experiment
fix agent drag & drop in world
Merge pull request #28 from Doik/datatarget_feedback

introduce datatarget_feedback
fix cross-nodespace-link creation
update client gate params after submitting form
some cleanup
implemented minecraft obstacle sensors
fix threshold, deactivate decay

decay should affect the links, not the activation
adopt frontend redraw condition to sheaves
minecraft obstacle experiment works
Merge branch 'master' of https://github.com/joschabach/micropsi2
added minecraft obstacle experiment to minecraft wiki
set default zoomFactor to 0.8 (thus compact view)
display cursor pos in world_status, object tooltip
focussing submit button in dropdown-only dialogs

after change of the last dropdown