Support Scala 2.12.10

[wangyum]

This PR makes it support Scala 2.12.10.

Scala 2.12.10 release notes:

• Fix regression in large string interpolations with non-String typed splices
• Revert "Generate shallower ASTs in pattern translation"
• Fix regression in classpath when JARs have 'a.b' entries beside 'a/b'

More details:
https://github.com/scala/scala/releases/tag/v2.12.10

[lightbend-cla-validator]

Hi @wangyum,

Thank you for your contribution! We really value the time you've taken to put this together.

Before we proceed with reviewing this pull request, please sign the Lightbend Contributors License Agreement:

http://www.lightbend.com/contribute/cla

[wangyum]

I have signed the CLA.

[wangyum]

cc @SethTisue @dwijnand

[SethTisue]

genjavadoc releases have usually been done by @2m, but he's no longer at Lightbend

@patriknw is there somebody else on the Akka team who could take on this responsibility...?

[raboof]

@SethTisue I think I've done one before, happy to give it a go again.

[dongjoon-hyun]

Thank you, @wangyum , @raboof and @SethTisue !

[raboof]

looking into #193 before releasing though

[dongjoon-hyun]

Great! Thank you all!