Please issue ERRFILE messages where appropriate

[scdbackup]

The event severity ERRFILE has a very low rank and shall transport plain file disk paths whenever an event of severity SORRY or above is related with an individual disk file.

No message text shall be added to the file path. The ERRFILE message shall be issued before the human readable message which carries the true event severity. That message shall contain the file path so it can be found by strstr(message, path)!=NULL.

Example:

ERRFILE : /my/bad/bad/filey
FAILURE : Cannot determine attributes of source file '/my/bad/bad/filey'