Merge branch 'master' into v0.12

Author: mwaskom

doc/_templates/layout.html

@@ -14,6 +14,7 @@
             Archive
         </a>
         <div class="dropdown-menu dropdown-menu-right" aria-labelledby="dropdownMenuLink">
+          <a class="dropdown-item" href="./archive/0.11/index.html">v0.11</a>
           <a class="dropdown-item" href="./archive/0.10/index.html">v0.10</a>
           <a class="dropdown-item" href="./archive/0.9/index.html">v0.9</a>
         </div>