Detail the Nebula sub-site creation process so far.

[NPDebs]

This issue exists to provide a progress update and detail the ongoing efforts to add Nebula to the website.

Changes so far:

• Add 'nebula' sub-folder to _data directory.
• Reproduce the folder structure currently in _data/openseeds.

    _data
          /openseeds
                ...
          /nebula
                /neb-1
                      metadata.yaml
                      projects.yaml
                      schedule.yaml
                /neb-2
                ...

Commits related to the sub-site creation can be found on this branch of my fork.

To be done:

• The people.yaml file is to be updated using a csv file from Civi.
• The other *.yaml files are to be populated from the Nebula planning sheet.
• Extracting data from the said planning sheet would require modification of the existing scripts.

More details to come...