- Unify all hash names as lowercase alphanumerics without punctuation.
- Legacy names continue to work but disappear from docs, they can be depreciated or dropped later.
- Make rclone hashsum print supported hash list in case of wrong spelling.
- Update documentation.
Fixes#5071Fixes#4841
Before this fix, FixRangeOption would substitute RangeOptions it
wanted to get rid of with with empty HTTPOption. This caused a problem
now that backends interpret HTTPOptions.
This fix subsitutes those with NullOptions which aren't interpreted as
HTTPOptions. This patch also improves the unit tests.
A Range request can never request 0 bytes however this change was made
to make a clearer signal that the limit means read to the end.
Add test and more documentation and fixup uses
