fix: purge instanceof Array from the codebase (#750)

Array.isArray works with arrays that came from other contexts like web
workers, instanceof Array wouldn't consider such array to be an array
even though it is perfectly valid array.

lib/shared/Configurator.js

@@ -63,7 +63,7 @@ class Configurator {
       if (typeof options === 'string') {
         this.options.filter = options;
       }
-      else if (options instanceof Array) {
+      else if (Array.isArray(options)) {
         this.options.filter = options.join();
       }
       else if (typeof options === 'object') {
@@ -588,7 +588,7 @@ class Configurator {
 
           // if needed we must go deeper into the object.
           if (show === false) {
-            if (!(item instanceof Array) && typeof item !== 'string' && typeof item !== 'boolean' && item instanceof Object) {
+            if (!Array.isArray(item) && typeof item !== 'string' && typeof item !== 'boolean' && item instanceof Object) {
               this.allowCreation = false;
               show = this._handleObject(item, newPath, true);
               this.allowCreation = checkOnly === false;
@@ -600,7 +600,7 @@ class Configurator {
           visibleInSet = true;
           let value = this._getValue(newPath);
 
-          if (item instanceof Array) {
+          if (Array.isArray(item)) {
             this._handleArray(item, value, newPath);
           }
           else if (typeof item === 'string') {

lib/timeline/Timeline.js

@@ -347,7 +347,7 @@ export default class Timeline extends Core {
     }
     else {
       // If groups is array, turn to DataSet & build dataview from that
-      if (groups instanceof Array) groups = new DataSet(groups);
+      if (Array.isArray(groups)) groups = new DataSet(groups);
 
       newDataSet = new DataView(groups,{filter});
     }