add guidance for study description (no links)

[mslarae13]

I can't remember if (no links) meant there wasn't a link... or we should remove the link..

But there is a link.

Do we have any written guidance or documentation on what a study description should be composed of?
Should we just pick a study with a good description and point people to it?

Suggestions:

• EcoFab
• Lybrand, NEON
• Stegen, river corridor
• Brodie, SFA

Completion criteria:

• Decide what we want the link to go to (study example or documentation)
• Update "Provide a description of your study. This should include some general context of your research goals and study design. For examples, please see existing study landing pages on the data portal." to something else on the submission portal.