[DF-748] Remove UNDOManager from project for MacOS. Remove UNDOManager files.
[DF-749] ExecuteAndRelease() method added to the CommandsManager. Executing and releasing of the commands were replaced with calling of this method.
[DF-754] IsAcceptNode method renamed to IsNodeAccepted
[DF-755] [DF-756] Fix not obvious code
[DF-571] Fix GetArrowsNode function