Changed documentation for ohc function and conditional if you make a mistake choosing the name of the Arctic region

Remove path to Virginie's home for cdfheatc-cfu as it is now the same as the one included in the module environment

Check if files already exist before creating symlinks (in case of rerunning remotely the script in the same workdir)

Remove user confirmation to overwrite old files (in case of rerunning remotely the script in the same workdir)

Correct 2nd bug in vertmeansal (valid_min) + change format of head and tail commands to make it work with older versions

cdo can change the naming of the dimensions which prevents cdftools to work properly; this is now corrected in the ohc function in case it happens

When requesting monthly mean outputs, the daily mean outputs will also be concatenated and monthly means built from these daily means

This test is not suitable anymore since the naming convention has changed in diags to be the same as MMO