Review all Darwin Core terms for suggestion

[peterdesmet]

Review all Darwin Core terms to see if they can be suggested for this dataset:

• [x] Root
• [x] Occurrence
• [x] Event
• [x] Location
• [x] Identification
• [x] Geological context
• [x] Taxon
• [x] Resource relationship
• [x] Measurement or fact: see issue #6