Add Scala Effekt and implement simple state example

[b-studios]

@kayceesrk what do you need to integrate Scala Effekt into CI? Since Scala Effekt is a library, it should be enough to just pick any Scala version and cache the dependencies:

language: scala
jdk:
- oraclejdk8
cache:
  directories:
    - $HOME/.ivy2/cache
    - $HOME/.sbt

[kayceesrk]

I think if you change the language at the top-level in the yaml file, then it changes the VM for all languages. It would be best if we set up per language matrix like https://stackoverflow.com/questions/27644586/how-to-set-up-travis-ci-with-multiple-languages. We can then run the makefile with appropriate env variables such that we only run tests for that particular language.

[b-studios]

I guess this now can be merged due to #6. Here is the most recent build rebased to master: https://travis-ci.org/b-studios/effects-rosetta-stone/builds/377729439 (I canceled the other languages to speed up the build :) )

[kayceesrk]

Lgtm! Have asked @andrejbauer to review as well.

[b-studios]

Ping :)