UPDATE 2:
All good!
I'm happy to announce that the latest release of the Go plugin for IntelliJ IDEA 1.0.0.alpha#134 supports a high degree of customization for highlighting (among many other things).
See the screenshots below on how it can look like:
Settings page
Possible configuration (don't worry, the default setup is much better ;) )
The release is available on the Github releases section (please read the docs before installing and install the zip file).
Also, I'd like to address some questions about the "alpha state" of the plugin.
Q: When will we have a stable, official release?
A: When it's good enough for us and our users.
Q: Should I install this at all? It has an alpha in it's name.
A: See below for the lengthy detail on why it's named alpha
Q: Should I install the version from the plugin manager? (0.9.15.3)
A: No, at this point 1.0.0-alpha releases are in a much better state than the 0.9.x releases.
Q: Is the plugin written in Go? Or can it be written in Go?
A: No. IntelliJ Platform is written in Java and can run a great deal of plugins that compile into a JVM compatible output (I believe, I've seen plugins written in Groovy, Scala and Kotlin) but Go is a no go for it
Q: Can you include oracle, golint, gofmt or other tools?
A: It depends on the tool itself. For example, for gofmt, while the plugin will have support for it initially, the functionality should be ported for the IntelliJ Platform and not rely on the tool itself. In case of oracle, that's one of the main features the Platform is providing for us native ;)
Q: Can you include X / Y / Z in the release? Or change A / B / C feature?
A: It all depends on the issue or feature you are requesting. It also depends if we can find people to help with the implementation. Or if you want / can implement it yourself even better.
Currently there are a great deal of efforts to bring the plugin in line with what the users of IntelliJ platform expect from a professional plugin. There's a bunch of work to be done to get there but some very talented people help us, the community, to get there.
The releases are currently labeled as alpha as they don't have all the functionality we'd like to have but it is already used by a lot of people in their day to day work.
You can view the list of 1.0 issues as well as a list of possible issues to be included in the 1.0 release.
A big Thank you! goes to Sergey (@ignatov) and Alexander (@zolotov) who are helping us quite a lot to bring this together as almost all you can see is their work in play, and also to our early adopters and people contributing to the plugin itself.