Add css-style-attr.vim

See also: http://www.w3.org/TR/css-style-attr

test/test.html

@@ -664,6 +664,11 @@
   display: reduced;
 }
 </style>
+<style style="display: auto">
+.style-attr {
+  display: auto;
+}
+</style>
 <style>
 .syntax-3 {
   display: auto;