checker for consistency between subblock-directory-information and subblock-segment

[ptahmose]

Is your feature request related to a problem? Please describe.

There is redundant information in the subblock-directory and the actual subblock (e.g. compression-mode, ...). There should be a checker which checks if the information is consistent and report differences.

Describe the solution you'd like

A new checker which compares the redundant information, and reports differences.

Describe alternatives you've considered

Additional context
example of such a document