Expose simplesession
Upgrade to Akka 2.3.0 and Spray 1.3.0
Added basic DSL for interpolated queries.

Also added a Shapeless HList-based mechanism for automatically
creating RowReader instances for Tuples. Next up: case classes and a DSL
for custom combinations of Reads instances at a row path.
Added first pass at query DSL.
More query interpolation changes.
Add more event mointoring stuff.
A few internal cleanup changes.

Better handling for query errors and retry, and now the sender for
query responses is the node/cluster instead of the temporary request actor.
Added some basic query and rate logging.
Attach sources to build.
Merge branch 'master' of github.com:vast-engineering/athena