Disk read failures should not disable tapes or drives

When there is a problem with a disk file, we don't want to disable the tape after 3 retries. In such case the tape is fully operational and there is no point in disabling it. Same argument applies for the tape drives.

Instead, we should implement a mechanism to disable the file itself.

Before changing the disable logic we should:

• add mandatory log parameters #229 (closed) to help us classify disk/tape errors for TAS.

See also discussions about:

• cataloging reasons for tape session failures #96
• review scheduler retry logic for archive and retrieve #37