Added file for ally-engine common imports

Author: Pooja0504

lib/checks/color/link-in-text-block-evaluate.js

@@ -6,7 +6,7 @@ import {
   incompleteData
 } from '../../commons/color';
 
-import { distinguishableLinkEvaluate } from '../../../../a11y-engine-core/lib/commons/distinguishable-link';
+import a11y_engine_commons  from '../../commons/a11y-engine-index';
 
 function getContrast(color1, color2) {
   var c1lum = color1.getRelativeLuminance();
@@ -41,7 +41,7 @@ function linkInTextBlockEvaluate(node) {
   this.relatedNodes([parentBlock]);
 
   if(options.a11yRule) {
-    return distinguishableLinkEvaluate(node, parentBlock);
+    return a11y_engine_commons.distinguishableLinkEvaluate(node, parentBlock);
   }
 
   // TODO: Check the :visited state of the link

lib/commons/a11y-engine-index.js

@@ -0,0 +1,6 @@
+import { distinguishableLinkEvaluate } from '../../../a11y-engine-core/lib/commons/distinguishable-link';
+
+let a11y_engine_commons = {};
+a11y_engine_commons.distinguishableLinkEvaluate = distinguishableLinkEvaluate;
+
+export default a11y_engine_commons;