Fixes and improvements in dragging of nodes.
Fixes and improvements in dragging of nodes.

mcanthony/jsoneditor,dbirchak/jsoneditor,walien/jsoneditoronline,2947721120/jsoneditor,cesarmarinhorj/jsoneditor,imkevinyang/jsoneditor,toanalien/jsoneditor,dbirchak/jsoneditor,liukd/jsoneditor,DavidGarciaCat/JSON-Editor-Online,amitdesai03/jsoneditor,liukd/jsoneditor,cobblers-children/jsoneditor,imkevinyang/jsoneditor,jayphelps/jsoneditor,imkevinyang/jsoneditor,amitdesai03/jsoneditor,mef/jsoneditor,cesarmarinhorj/jsoneditor,2947721120/jsoneditor,2947721120/jsoneditor,DavidGarciaCat/JSON-Editor-Online,cobblers-children/jsoneditor,liukd/jsoneditor,mcanthony/jsoneditor,tomalec/jsoneditor,dbirchak/jsoneditor,mef/jsoneditor,josdejong/jsoneditor,jayphelps/jsoneditor,shuai959980629/jsoneditor,mcanthony/jsoneditor,shuai959980629/jsoneditor,tomalec/jsoneditor,shuai959980629/jsoneditor,toanalien/jsoneditor,walien/jsoneditoronline,cesarmarinhorj/jsoneditor,cobblers-children/jsoneditor,walien/jsoneditoronline,toanalien/jsoneditor,jayphelps/jsoneditor,josdejong/jsoneditor,amitdesai03/jsoneditor,mef/jsoneditor