bugfix: do not display connectors on port position change if not needed by the decorator
bugfix: do not display connectors on port position change if not needed by the decorator

Former-commit-id: f4f3253ea21e9c72d362d1eb331bccf31fc372d1
webgme/webgme-engine,webgme/webgme-engine,webgme/webgme-engine