partclone.info: show the image's details

Show the details like:
- partclone's version used to create the image
- bitmap mode
- checksum options

Signed-off-by: Patryck Rouleau <pfrouleau@gmail.com>
partclone.chkimg: check only the image's size when it does not contains checksums

Signed-off-by: Patryck Rouleau <pfrouleau@gmail.com>