open fun getScalaVersion(scalaJar: File): String
Determines the version of a Scala Jar file (scala-compiler, scala-library, scala-jdbc, etc.). If the version cannot be determined, or the file is not a Scala Jar file, null is returned.
Implementation note: The version is determined by parsing the file name, which is expected to match the pattern 'scala-[component]-[version].jar'.
Return
the version of the Scala Jar file