Suunto SDE updates, take 178: add weight and visibility info

This converts the weight information into subsurface weights, and also
adds visibility info (if it exists) into the notes for the dive.

More fall-out from me looking at the nasty suunto xml files, now that I
have a few that actually have some info that isn't just from the
computer download.

Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>