Documentation updates for 2022 WP OBS developments

nemo/nemo#126 (closed) describes changes to the NEMO OBS and ASM code as part of the 2022 WP, primarily to make the OBS interface more generic. This involves changes to the OBS namelist, necessitating documentation updates, to be covered by this issue.

To upload designs, you'll need to enable LFS and have an admin enable hashed storage. More information