Add support for IntelliJ products

[pindab0ter]

IntelliJ offers a host of very popular IDEs. I imagine it would not be an easy task, but supporting their products would be incredibly interesting to a lot of people.

[mjswensen]

Thanks, @pindab0ter ! You are right, I suspect there would be many interested. I am going to close this in favor of the duplicate issue logged over at themer (the repository for themer-gui's core engine).

[mjswensen]

Good news @pindab0ter , the v0.17.0 release (released this morning) adds support for JetBrains IDEs!