ISGCIUndomanager with amended methods like undo..; adjusted help.html; maybe should have to be improved
ISGCIUndomanager with amended methods like undo..; adjusted help.html; maybe should have to be improved #2
merge undomanager with leokraemer develop
there are bugs, when drawing graphs and using undo, but its not an undo problem
Merge pull request #77 from byebb/develop

Develop branch byebb