Don't mention default EEx engine twice; add a note about it in the code
Merge pull request #2193 from alco/eex-doc

Don't mention default EEx engine twice; add a note about it in the code
Use esl package to get erlang 17.0 on travis
Merge pull request #2194 from elixir-lang/travis-esl-package

Use esl package to get erlang 17.0 on travis