Operator group is not highlighted

[mkalinski]

As seen in the attached screenshot. Operator group has the same color as base text. This is a problem for languages which have operators which are text keywords (ex. "sizeof")

I'm using Neovim 0.1.5-dev on Ubuntu 16.

[Ramzi Akremi]

Thanks for your feedback and also opening the issue. I have changed the Operator highlighting in order to use of accent color.
Enjoy