SBT, 2.11, and quasiquotes (WIP)

Hi @julienledem,

I just took a quick stab at this during a couple of back-to-back meetings. I've added the SBT build config, made a few changes to get the project to compile on 2.11, fixed all the deprecation warnings I could while still keeping 2.10 support, and changed a couple of the macros to use quasiquotes (mostly as a demonstration—I ran out of time, but the rest would be pretty easy to finish up, and I'm happy to try to make some time for it if you're interested).

in which case does ArrowAssoc apply?