Various sync fixes: - resolve subdbs before applying delta - don't call a map entry modified unless the (encoded) value differs - provide a means to merge two db histories into one (melding)
Various sync fixes:
- resolve subdbs before applying delta
- don't call a map entry modified unless the (encoded) value differs
- provide a means to merge two db histories into one (melding)

joansmith/tripleplay,tomfisher/tripleplay,joansmith/tripleplay,tomfisher/tripleplay,tomfisher/tripleplay,joansmith/tripleplay,tomfisher/tripleplay,tomfisher/tripleplay,joansmith/tripleplay,joansmith/tripleplay