build logic + better publishing

[RBusarow]

This introduces a convention plugin to handle publishing for the main build and the gradle-plugin build. It mostly just uses the newer base plugin, and most of the configuration still just comes from gradle.properties. The important difference is that each module now sets its artifact ID, pom name, and pom description from inside the DSL, such as:

publish {
  configurePom(
      artifactId: 'annotations-optional',
      pomName: 'Anvil Optional Annotations',
      pomDescription: 'Optional annotations that we\'ve found to be helpful with managing larger dependency graphs'
  )
}

This allows us to just symlink the gradle-plugin/gradle.properties without worrying about breaking publishing.

I tried to avoid yak-shaving. There's lots more than can be moved to conventions, but this is enough to unblock local publishing for integration tests.

[vRallev]

"library" is so generic, why not com.squareup.anvil.library?

[RBusarow]

In my head, I consider local convention plugins to be closely related to precompiled script plugins or built-in plugins. Since the precompiled plugins often have short names and the built-in ones all have short names, I'm mostly convinced that this type of plugin should also have a short name.

It's not something I feel strongly about, though. If you're unconvinced, I can change it.

[vRallev]

I don't feel strongly either. But my first impression was "what's that and where is it coming from". Searching only for "library" also takes longer.

[RBusarow]

I will continue to slightly lean in the other direction, but the IDs have now been lengthened.

[vRallev]

Sneaky

[RBusarow]

Hiding in plain sight!

Actually, I forgot about this or I would have called it out. It has lots of excellent build-logic yak-shaving applications.