Mark curator-test and other deps as provided instead of optional

optional deps are pulled in by sbt assembly, apparently.
in this case we are pretty sure other projects pull in what has been marked provided.
Upgrade to SBT 0.13 / cloudbees-sbt plugin 1.3.0
Revert "Mark curator-test and other deps as provided instead of optional"

This reverts commit 1c5525c222c51d1ab807571b8a8d0eb0a6f78e03.
Split into two projects: core and test
Merge pull request #6 from socrata/velvia/dont-pull-slf4j-simple

Looks good to me.  Is this the first project we're using .sbt-based multi-project code?