Maven integration

[tobias-]

Integration that lets you build the library (not the demo app).

Handles install properly, but not deploy, so extra maven config is needed for that.

[billmag]

I'd like to use 2 space tabs on this instead of tab characters, all of the other resources in our repository do so.

Also, I can probably merge the deploy configuration from our internal version of this project to fill this out. Any specific concerns you'd have with deployment?

[tobias-]

Since we need to get the binary blob installed I do some hocus pocus in the root pom.xml, hence my concern for the deploying.

Right now we include appboy as a git subtree and build it together with the rest of our app, so we don't need deploy, but I assume most people will just want to build once and auto-deploy the .apklib and the .jar to a remote repository (or even just get a pre-built from a repository).

[billmag]

Quick note -- you can now install the UI library as an AAR into your local maven repository with ./gradlew install. If that satisfies your use case here, you can probably get rid of this pom file and close the pull request.

[tobias-]

Ok, we're keeping it locally, but there's no point in this request anymore