added pinning UI to inline

lms/static/sass/_discussion.scss

@@ -2450,6 +2450,13 @@ body.discussion {
       padding-right: 5px;
       font-style: italic; 
     }  
+
+.discussion-pin-inline {
+      font-size: 12px;
+      float:right;
+      padding-right: 5px;
+      font-style: italic; 
+    }  
     
 .notpinned .icon
 {
@@ -2477,4 +2484,9 @@ body.discussion {
 .notpinned span {
   color: #888;
   font-style: italic;
+}
+
+.pinned-false
+{
+display:none;
 }
\ No newline at end of file

lms/templates/discussion/mustache/_inline_thread.mustache

 <article class="discussion-article" data-id="{{id}}">
-<div class="pinned-{{pinned}}"></div>
     <div class="thread-content-wrapper"></div>
 
     <ol class="responses post-extended-content">

lms/templates/discussion/mustache/_inline_thread_cohorted.mustache

 <article class="discussion-article" data-id="{{id}}">
 <div class="group-visibility-label">{{group_string}}</div>
-<div class="pinned-{{pinned}}"></div>
+
     <div class="thread-content-wrapper"></div>
 
     <ol class="responses post-extended-content">

lms/templates/discussion/mustache/_inline_thread_show.mustache

@@ -3,6 +3,9 @@
     <header>
         <a href="#" class="vote-btn discussion-vote discussion-vote-up" data-role="discussion-vote" data-tooltip="vote"><span class="plus-icon">+</span> <span class='votes-count-number'>{{votes.up_count}}</span></a>
         <h3>{{title}}</h3>
+<div class="discussion-pin-inline pinned  pinned-{{pinned}}" data-tooltip="This thread has been pinned by course staff.">                
+<i class="icon"></i><span class="pin-label">Pinned</span></div>
+
         <p class="posted-details">
             {{#user}}
             <a href="{{user_url}}" class="username">{{username}}</a>