subjects page: add sort function for subjects before grouping

src/app/subjects/subjects.component.ts

@@ -148,6 +148,7 @@ export class SubjectsComponent {
         //this.getDivContents();
         this.getPageContents();
         this.subjects = community.subjects;
+				this.subjects.sort();
 				this.groupSubjects();
         this.showLoading = false;
       }