-- the underlying data structure is still present, but until I decide what to do for the extensible system I've completely disabled the subsystem
-- Added code to merge Samples, so that a mostly full record can be merged with a consistent empty record. If the two records are inconsistent, an error is thrown
-- addSample() in Sample.class now invokes mergeSample() when appropriate
-- Validation types are now only STRICT or SILENT
-- Validation code implemented in SampleDBBuilder
-- Extensive unit tests for SampleDBBuilder
-- Passes significiant unit tests
-- Implicit sample creation for mom / dad when you create single samples
-- Continuing cleanup of Sample and SampleDataSource