`scripted` tests broken on `series/0.6.x` branch

[metasim]

Steps to reproduce:

1. Clone repo and check out the series/0.6.x branch
2. Run sbt ';tutPublishLocal; scripted'

It also turns out the the Travis build doesn't actually run the scripted tests when the Scala version isn't 2.11.x. Sbt 1.x plugins run on Scala 2.12.x

I'd also suggest the plugin be upgraded to support cross building the plugin, according to this. Should address this issue and make deployment easier.

[metasim]

cc: @larsrh

[metasim]

PS: adding the following to the build should eliminate the need to run tutPublishLocal manually before running scripted:

scriptedDependencies := (scriptedDependencies dependsOn(publishLocal in core, publishLocal in plugin)).value