Testing format import for tests

If an external site wants to migrate from its tape storage solution to CTA, one of the requirements would be to import its current tapes in CTA catalogue and work on adapting cta-taped to somehow read the tape.

No need for physical tapes to validate the format: MHVTL binary tape import should allow to perform a big chunk of the format validation in developer environment.

The base idea is:

• create a binary dump of a tape using dd on sg tape device
• inject the binary dump to an MHVTL tape using dd
• inject minimal file information in TAPE_FILE table
• drive DOWN, read the tape using cta-readtp