Add disk read veryfication

[marcinzawa]

This is a change request (enhancement).

Can you add an option to verify written content. After writing some bytes, for example 0xaa, dskwipe should read the full disk and verify if the data matches.

simiar solution is implemented in linux tool "badblocks -vws".

Thanks!

[bilogic]

@marcinzawa

Can help me understand what is the purpose of doing this?