Add the support for multiple plugins inside a single Gradle project

[ivandev0]

I would like to have a single Gradle project with the following structure

- shared    <--|
- plugin1    --|
- plugin2    --|

Here plugin1 and plugin2 depend on the shared module. I can build and publish each plugin separatly as completely different plugins. I would guess that this can be easily done with Gradle subprojects, but it is quite hard to do a proper setup. If this is already implemented, it would be nice to have an instruction in the documantation.

[SingingBush]

That should be doable but will take some effort in the Gradle build.

We kind of have this for intellij-dlanguage however we effectively bundle plugin1 in to plugin2 and just ship plugin2 to the repo.

Our codebase grew a lot over time so in an attempt to break things up the dub plugin started in a separate repo and was shipped separately with a dependency on net.masterthought.dlanguage being installed. We now moved the source for the dub plugin into our main repo and have also added source for our sdlang plugin. Both of these are complete plugins in themselves but at the minute we bundle them into the main artifact to upload them as one bundle. I think with a little effort in the Gradle build it could be configured to have them ship independently.