Add methodology section

[callumrollo]

Proponents:
Moderator: @OceanGlidersCommunity/format-mantainers

Type of PR

• Addition that does not require change in the current structure.

Related Issues

#143

Release checklist

• Approved by at least two members of the committee?
• There were modifications after the review approvals? If so, please
  ask reviewers to update their review.
• Proponents and moderador should explicitly agree that it is ready to
  to merge.
• The moderador is the one in charge to actually merge or close this PR
  according to the final decision.

For maintainers

• Update the moderator with a volunteer from the committee. It would be
  best to have one single moderator to guide and help this PR to move
  forward. It is OK to update the moderador pass it to another one.
• Confirm that the associated branch was deleted after the merging.
• Wrap-up and close the related issues.

[callumrollo]

This PR moves the history section to the history doc and adds a methodology section based on the text by @vturpin in #143

[glidermann]

There are a lot of problems with the English..I don't have time now though.

[callumrollo]

I've cleaned up the spelling and grammar @glidermann

[justinbuck]

This is as per discussions in the OG 1.0 meetings

[callumrollo]

@glidermann can you re-review this when you have time? Currently merging is blocked

[glidermann]

The changes are fine...can someone remind me: did we agree to keep the Endorsement section? I don't think it is necessary, and maybe not the right wording...they participated and generally agreed with this effort, but have not seen and formally endorsed the final product.

[callumrollo]

Thanks for the quick review! The endorsement section was removed in #146

[glidermann]

Thanks...I was confused by the text in this branch I guess, just below this PR.