clean up and simplify support for bottom navbar by automagically turning dropdowns into dropups

less/dropdowns.less

@@ -126,7 +126,9 @@
 // Allow for dropdowns to go bottom up (aka, dropup-menu)
 // ------------------------------------------------------
 // Just add .dropup after the standard .dropdown class and you're set, bro.
-.dropup {
+// TODO: abstract this so that the navbar fixed styles are not placed here?
+.dropup,
+.navbar-fixed-bottom .dropdown {
   // Reverse the caret
   .caret {
     border-top: 0;

less/navbar.less

@@ -275,7 +275,7 @@
   }
 }
 // Menu position and menu caret support for dropups via extra bottom-up class
-.navbar .dropdown-menu.bottom-up {
+.navbar-fixed-bottom .dropdown-menu {
   &:before {
     border-top: 7px solid #ccc;
     border-top-color: rgba(0, 0, 0, 0.2);