Allow for population of partially created POJOs

Currently Jetedge will attempt to populate and entire POJO unless otherwise specified. The builder should be expanded to take in an object that is partially made and a new PojoAnalyzer should be constructed that only attempts to populate fields that are null.

Start by locating the builder and the existing POJO analysis/population path, then inspect how fields are currently selected for population. Done means the builder accepts a partially created POJO, preserves non-null fields, and populates only fields that are null.

Written by the indexing model from the issue text.