Add isSupported method zenorocha#355

Author: itaisteinherz

dist/clipboard.js

@@ -728,6 +728,20 @@ module.exports = E;
                     this.clipboardAction = null;
                 }
             }
+        }], [{
+            key: 'isSupported',
+            value: function isSupported() {
+                var action = arguments.length > 0 && arguments[0] !== undefined ? arguments[0] : ['copy', 'cut'];
+
+                var actions = typeof action === 'string' ? [action] : action;
+                var support = !!document.queryCommandSupported;
+
+                actions.forEach(function (action) {
+                    support = support && !!document.queryCommandSupported(action);
+                });
+
+                return support;
+            }
         }]);
 
         return Clipboard;