create test language and sandbox for hybrid editor
add test concepts
add test model and editor for root concept
integrating jetpad editor into MPS first step
modifying descriptor generator to allow manual editor specification by implementing BaseLaguage classes
simple generic view cell implemented
manually specifying second editor for the test language -> diagram
project files
add jetpad.Editor module
perform showing diagram blocks
move Jetpad.Editor to languages/core/stub
make myView in GenericViewCell private
create cell for each view
add connectors, draw lines
fix NPE
removing unnecessary model root
cleaning up DiagramEditor implementation
optimize imports & reformat
refactor block editor
make