Added creationDate and creationTime to keywords

[jesper-friis]

Description

These have been used in the documentation in MatCHMaker and PhysMet

Type of change

• Bug fix and code cleanup
• New feature
• Documentation update
• Testing

Checklist for the reviewer

This checklist should be used as a help for the reviewer.

• Is the change limited to one issue?
• Does this PR close the issue?
• Is the code easy to read and understand?
• Do all new feature have an accompanying new test?
• Has the documentation been updated as necessary?
• Is the code properly tested?

[codecov]

Codecov Report

✅ All modified and coverable lines are covered by tests.
✅ Project coverage is 84.77%. Comparing base (a93b12a) to head (6c3f6d9).

Additional details and impacted files

@@           Coverage Diff           @@
##           master     #480   +/-   ##
=======================================
  Coverage   84.77%   84.77%           
=======================================
  Files          30       30           
  Lines        4690     4690           
=======================================
  Hits         3976     3976           
  Misses        714      714           

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[francescalb]

Is this smart? To have in our standard vocabulary several annotations that mean the same or that we will at least be using interchangeably? There is also dcterms:issued

[jesper-friis]

Is this smart? To have in our standard vocabulary several annotations that mean the same or that we will at least be using interchangeably? There is also dcterms:issued

Good question. creationDate (dcterms:created) was included since users asked for it. It is the date when the resource was created. releaseDate (dcterms:issued`) is the date when the resource was first released.

The properties have different meanings, but it could very well be that releaseDate is sufficient.