Improvements to queryNode and scanNode logic.

Ensured that splits encode the specific aerospike server ndoe to
connect to.

Ensure that the hostname in the split is transferable between hadoop
nodes (not 127.0.0.1).

Improved diagnostics in the scanNode and queryNode paths.
Merge pull request #2 from citrusleaf/query-node-squashed

Improvements to queryNode and scanNode logic.