Site file updates

[singhd789]

In the site files, tasks create output directories in the pre-script. This structure was followed for the generic.cylc update.

However, there are some reservations about creating directories (non-site aspects) in site files.

One Solution:
Output directories can be made be made in either the flow.cylc task themselves (as pre-script) or as the first thing in the task script.

They can be made in the flow.cylc if there are no other modules that are gfdl site specific are loaded (in this case, I believe the site file pre-script is used versus the pre-script already defined in the flow.cylc)

Ex: SPLIT-NETCDF
flow.cylc:

fre-workflows/flow.cylc

Line 729 in 9483ee9

pre-script = mkdir -p $outputDir

ppan.cylc:

fre-workflows/site/ppan.cylc

Line 74 in 9483ee9

pre-script = module load cdo nco && mkdir -p $outputDir