allow to deploy_manifest_lines in scala_binary and scala_test

Hi,

Java rules has this useful ability to add manifest lines: https://bazel.build/versions/master/docs/be/java.html#java_binary.deploy_manifest_lines

Our rules (`scala_binary` and `scala_test`) lack this property. We need to allow this behavior to happen in our rules as well.

Start by locating the scala_binary and scala_test rule definitions and compare their attributes with the Java rules documentation for deploy_manifest_lines. Trace how the property is propagated, then verify that both rules accept it and produce the requested manifest lines.

Written by the indexing model from the issue text.