Changed the order of parameters in getScala method.
Changed the key name to scalaOrganization (scala-organization).
Augmented description of the key.
Minor fixes.
Adding scalaOrg key that specifies organization (artifactId) of scala used in the project. The change does not affect version checks for dependecies and LauncherConfiguration.
Modified scalaProvider cache in Launcher to use (scalaOrg, version) as a key.
Downloaded jars are stored in the folder scala-.../lig-<scalaOrg> if scalaOrg is not default.
scala-org is an advanced setting so it can not be used in build.sbt.