Option to exclude transitive ivy dependencies

[raskam]

Currently Dep only has an option to configure coursier attributes, but there's no way to configure coursier exclusions.

Right now I'm using implicits to achieve this:

  implicit class RichDep(dep: Dep) {
    def exclude(exclusions: (String, String)*): Dep = {
      dep match {
        case d: Dep.Java => d.copy(dep = d.dep.copy(exclusions = d.dep.exclusions ++ exclusions))
        case d: Dep.Scala => d.copy(dep = d.dep.copy(exclusions = d.dep.exclusions ++ exclusions))
        case d: Dep.Point => d.copy(dep = d.dep.copy(exclusions = d.dep.exclusions ++ exclusions))
      }
    }
  }

And usage:

ivy"org.quartz-scheduler:quartz:${V.quartzV}"
  .exclude(
    "com.mchange" -> "c3p0",
    "com.zaxxer" -> "HikariCP-java6"
  )

Better would be of course to modify the Dep directly. I could make it into PR if you like the way it is implemented.

[lihaoyi]

@raskam you can always fall back to passing in a coursier.Dependency to ivyDeps; could you try configuring one with the exclusion you want and seeing if that works?