Expose expected values for validation errors

[apoorva-sriv]

For example, CONTROL_COUNT_DOES_NOT_MATCH_ACTUAL_COUNT should provide the count that it computed—similarly for all the other errors in EDIStreamValidationError. This will make debugging through logs easier.

[MikeEdgar]

This may be a bit more complicated :) For most of the validation errors, the relevant data can be obtained via the EDIStreamReader interface.

The control counts are different though, since, as you mention, it's calculated by the reader. This may require a new method on the stream reader interface to access the individual counts.