Eng4791, eng4674

Address two java client library issues induced by pulling a constant from VoltDB.java into ParameterSet:
1) Stop running the static {} block in VoltDB.java that sets the timezone to GMT
2) Stop pulling in zookeeper dependencies

Accomplish this by pushing said constant to a place where it can be used without unexpected side effects.  Eventually we should push more constants there but I need to get this to a customer and who knows what might secretly depend on the side effects?

This doesn't address the additional external jar requirements of the client library.

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