Refactor .list-inline and .list-unstyled

* Instead of shared and separate CSS, isolate by class for easier mixin-ability
* .list-unstyled is now used as a mixin in .list-inline

docs/assets/css/bootstrap.css

@@ -546,7 +546,11 @@ li {
   line-height: 20px;
 }
 
-.list-unstyled,
+.list-unstyled {
+  margin-left: 0;
+  list-style: none;
+}
+
 .list-inline {
   margin-left: 0;
   list-style: none;

less/type.less

@@ -126,18 +126,20 @@ li {
 }
 
 // List options
+
 // Unstyled keeps list items block level, just removes list-style
-.list-unstyled,
-// Inline turns list items into inline-block
-.list-inline {
+.list-unstyled {
   margin-left: 0;
   list-style: none;
 }
-// Single-line list items
-.list-inline > li {
-  display: inline-block;
-  padding-left: 5px;
-  padding-right: 5px;
+// Inline turns list items into inline-block
+.list-inline {
+  .list-unstyled();
+  > li {
+    display: inline-block;
+    padding-left: 5px;
+    padding-right: 5px;
+  }
 }
 
 // Description Lists