swift234

Additional conformance changes for Measurement and unit tests to verify comparison and equality

After speaking with the current owner of Measurement, the most sensible path is to at runtime verifty the conformance of Units to a specific dimension since we cannot directly check at compile time. If at a future point in time a more specific comparitor can be added that can restrict the comparison to measurements in a specific dimension without causing equatable failures we may want to revisit this. However as it stands this preserves the most reasonable implementation of comparison of disperate measurement unit types while preserving the expected logic of conversions within that dimension.