Update to MAPv4 public draft

This should be in line with the draft at: https://docs.google.com/document/d/1Jh8ULpw0jb8kyxV-Ygw9U0n-XqXkM6_V3jxfmnkebqo/edit#
Any opposition to calling this `:temporal`?  (see comment on `:place` vs `:spatial` vs. `:spatialCoverage`)