scalafmt format

[carlosms]

Partially replaces #74, see #74 (comment).

This branch was created from #86, the relevant commit is just bd39545.

[bzz]

Looks great, let's finish and merge the linter first and then get back and

[smola]

Before merging scalafmt and perform any reformatting, we should discuss if we would like to do for default or intellij styles. I have also seen that the following might need to be added to enforce line length:

# disable case arrow alignment, it breaks line length
align.tokens = []

It would be desirable if:

• Our .scalafmt.conf does not conflict with previous scalastyle-config.xml (actually, both might be kept, since scalastyle checks for stuff scalafmt doesn't.
• It produces minimal reformatting on existing code (this might not be possible, but...).
• We can push this company-wide for Scala projects.

[smola]

I discussed this offline with @bzz. Just to be clear: I don't want to block this, but if you plan to produce massive reformatting with it (e.g. >1k lines across multiple files), let's double check with others.