[BUG] tools/coredumper: wrong formatting

[mmaka1]

Describe the bug
There are a couple of issues with the format of the output:

• -l options does not work unless verbose mode is on, but the usage does not mention that,
• verbose mode require tty (should not) which makes it less useful when piped with 'more' for example,
• core header fields should be printed separately and clearly described as the core header, while they are mixed with cpu registers now,
• some rows begins with | while others begins with #, marks are unclear.

[abonislawski]

all done in PR #1220