revid & device/file/file.go: Loop feature appears to no longer work

[Saxon Milton]

The Loop feature when turned on ensures that at input file is looped, i.e. when we get EOF, we seek to the beginning of the file and read over again. This now appears to no longer work, need to investigate and correct.

[Saxon Milton]

Merged in fix-loop (pull request #483)

revid & device/file: removing Loop mode which was conflicting with Loop variable, and improve file input with logging and robustness

Resolves issue #374

Approved-by: Trek Hopton

→ <<cset f9fddcf0e893>>