NOJIRA: fix artifact names to follow Scala convention

Scala maven artifacts follow convention of appending Scala
compiler version number to the name. This is necessary
as binaries across Scala major version are not compatible.

Signed-off-by: Anand Avati <avati@redhat.com>
Unfortunately variables do not work. See
https://github.com/apache/spark/pull/996#discussion_r15679675 for similar
discussion.