Maestro API cleanup

[jng]

This is an umbrella ticket for general cleanup of various bits of the Maestro API:

A rough list of things that need to be done:

• Remove the FLEE-based Expression Engine API. This feature isn't advertised much and performing feature queries with computed properties achieves the same effect.
• Remove ArgumentParser class. There are nuget-fetchable and battle-tested libraries that do a better job.
• Reference NetTopologySuite proper from NuGet instead of our internal ILMerged NTS assembly