Multiple UI Improvements (#3804)

* PLT-3834 - Updating Manage members modal for mobile

* PLT-3792 - Making compact view compatible with search and flagged posts RHS

* PLT-3910 - Improving suggestions separator

* PLT-3769 - Enabling markdown headings in compact view

* Updating view members text in en..json

* Removing shouldcomponentupdate from search_results_item.jsx

webapp/sass/layout/_post.scss

@@ -545,8 +545,8 @@ body.ios {
         }
 
         .markdown__heading {
-            font-size: 1em;
-            margin: 0 0 7px;
+            clear: both;
+            margin: 7px 0;
         }
 
         .post__header {