AddDeps should default to the default configuration, not compile

The AddDeps magic (using Coursier) currently requests the compile configuration instead of the default configuration. The dependencies shouldn't be those needed to compile, but should be the runtime dependencies, which are normally pulled in by the default configuration. We ran into issues with this because runtime dependencies are not included.

In addition, I'd like to add --ivy-configuration and --classifier options to give users control over what gets used.