Add reminder text above send email button

lms/static/sass/course.scss.mako

@@ -64,6 +64,7 @@
 
 // instructor
 @import "course/instructor/instructor";
+@import "course/instructor/email";
 
 // discussion
 @import "course/discussion/form-wmd-toolbar";

lms/static/sass/course/instructor/_email.scss

+.submit-email-action {
+  margin-top: 10px;
+  line-height: 1.3;
+
+  ul { 
+    margin-top: 0;
+    margin-bottom: 10px;
+  }
+}
+

lms/templates/courseware/instructor_dashboard.html

@@ -464,9 +464,14 @@ function goto( mode)
       <textarea cols="100" id="id_message" name="message"></textarea>
     %endif
     </p>
-    <p>
-    <input type="submit" name="action" value="Send email">
-    </p>
+    <div class="submit-email-action">
+      Please try not to email students more than once a day. Important things to consider before sending:
+      <ul>
+        <li>Have you read over the email to make sure it says everything you want to say?</li>
+        <li>Have you sent the email to yourself first to make sure you're happy with how it's displayed?</li>
+      </ul>
+      <input type="submit" name="action" value="Send email">
+    </div>
 %endif
 
     </form>