removing duplicate reset filter since we changed the main button to use...

removing duplicate reset filter since we changed the main button to use buttonBackground mixin, per #2024

docs/assets/css/bootstrap.css

@@ -1737,7 +1737,6 @@ table .span12 {
   -moz-box-shadow: inset 0 1px 0 rgba(255, 255, 255, 0.2), 0 1px 2px rgba(0, 0, 0, 0.05);
   box-shadow: inset 0 1px 0 rgba(255, 255, 255, 0.2), 0 1px 2px rgba(0, 0, 0, 0.05);
   cursor: pointer;
-  filter: progid:DXImageTransform.Microsoft.gradient(enabled = false);
   *margin-left: .3em;
 }
 .btn:hover,

less/buttons.less

@@ -25,7 +25,6 @@
   cursor: pointer;
 
   // Give IE7 some love
-  .reset-filter();
   .ie7-restore-left-whitespace();
 }