Added methods to test for the existence of certain entities without retrieving them. Now swallowing error code associating datasets with images when association already exists

start and end times are now parsed to ISO-8601 timestamps with incumbent exception handling and reporting

Added support for new fields and smarter merges to datasets.  Added support for globally omitted fields to domain objects

Added better exception handling and more useful error messages (work in progress). Added ability to associate a dataset with a figure

Fixed example code. Added support for ready_to_publish flag in sync. Refactored sync to bring some level of order

Removed statically-defined header var. Added test_login methods. Adding exception handling for more useful error messages; more to follow