Request for Go language (https://golang.org/) syntax highlighting to be included in the official distribution.

There are some user defined language files that could be brought in e.g. https://github.com/tlowry/npp-golang/blob/master/golang.xml

Previous issues have requested this but have been steered down the UDL route (#3037 #4778 #2574).

It's been consistently picking up in popularity over the last few years, so I think it would be beneficial to include it (https://hackernoon.com/googles-go-programming-language-is-going-places-by-how-far-bwbb3dnl).

It's more popular/relevant than a few of the languages that are supported at the moment.