Merge: Workaround nitlight

nitlight was broken when `is cached` was used because highlight does not like AST transtormations.

This workaround justs disable the `cache` phase until something better is found.

http://nitlanguage.org/code2/nitserial.html#nitserial#MModule#serializable_type

Pull-Request: #855
Reviewed-by: Alexandre Terrasa <alexandre@moz-code.org>