#356 Fixing issue where dropping an item on the right end of a horizontally layed out drop zone does not add the item

Sortable.js

@@ -591,7 +591,7 @@
 
 
 				if ((el.children.length === 0) || (el.children[0] === ghostEl) ||
-					(el === evt.target) && (target = _ghostInBottom(el, evt))
+					(el === evt.target) && (target = _ghostIsLast(el, evt))
 				) {
 					if (target) {
 						if (target.animated) {
@@ -1086,11 +1086,11 @@
 
 
 	/** @returns {HTMLElement|false} */
-	function _ghostInBottom(el, evt) {
+	function _ghostIsLast(el, evt) {
 		var lastEl = el.lastElementChild,
 				rect = lastEl.getBoundingClientRect();
 
-		return (evt.clientY - (rect.top + rect.height) > 5) && lastEl; // min delta
+		return ((evt.clientY - (rect.top + rect.height) > 5) || (evt.clientX - (rect.right + rect.width) > 5)) && lastEl; // min delta
 	}