Tests for add-curie.

add-curie can take either parameters to create or a prebuilt, like
add-link was changed to do.
add-curie implemented

It's 2/3 assertions! Uh, might I be going overboard...?
Tests for add-curies.
Implemented add-curies.
Tests for add-property.
Implemented add-property.
Tests for add-properties.

The function can take:
  map
  coll
  key + value parameters
Implemented add-properties.

Use like:
(add-properties resource [:key "val" :otherkey "otherval"])
(add-properties resource {:foo "bar :a "b"})
(add-properties resource :first "first value" :second "second value")