[ADF-1769] Added JSDocs to services (#2937)

* [ADF-1769] Added JSDocs to services

* Removed JSDoc return directives from doc comments

lib/core/services/highlight-transform.service.ts

@@ -21,6 +21,12 @@ export interface HightlightTransformResult {
 }
 export class HighlightTransformService {
 
+    /**
+     * Searches for `search` string(s) within `text` and highlights all occurrences.
+     * @param text Text to search within
+     * @param search Text pattern to search for
+     * @param wrapperClass CSS class used to provide highlighting style
+     */
     public highlight(text: string, search: string, wrapperClass: string = 'highlight'): HightlightTransformResult {
         let isMatching = false,
             result = text;