Media query support for 'hover' (see issue #128)

Author: andyrichardson

grammars/css.cson

@@ -1163,6 +1163,7 @@
           | scan
           | orientation
           | display-mode
+          | hover
         )
         |
         # Deprecated features
@@ -1222,6 +1223,7 @@
         | standalone
         | minimal-ui
         | browser
+        | hover
       )
       (?=\\s|\\)|$)
     '''