All exported funcs in api.go are now documented
Several poorly named methods of API and Cluster were renamed. Particularly, the
word Fragment was often changed to Slice in cases where it was really a slice
being specified and not a fragment.
several methods which received or returned internal data structures have been
refactored to be more opaque.
Deprecation logging was added to input definition methods.
had to update test which was relying on a fake ClusterStatus implementation. Now
the status endpoint uses information directly from Cluster.Nodes and
Cluster.state - which is what Server (the usual ClusterStatus impl) uses, so it
should make no difference for real clusters.
don't export QueryValidationSpecRequired
add docs to some methods
simplify /debug/vars handling using expvar.Handler()
implement Version in API and simplify
