Add query metrics.

-Metrics are optional (default off), and an example balboa configuration is commented-out in reference.conf
-Only balboa is currently allowed as a metric provider, but this is easy to change down the road
Update balboa version
Move most of balboa client out to balboa
Update balboa version
Merge branch 'andrewburnell/metrics'

Conflicts:
	project/SodaFountainLib.scala
	soda-fountain-lib/src/main/scala/com/socrata/soda/server/SodaFountain.scala
	soda-fountain-lib/src/main/scala/com/socrata/soda/server/config/SodaFountainConfig.scala
	soda-fountain-lib/src/main/scala/com/socrata/soda/server/resources/Resource.scala