ID_Start, ID_Continue,and stability extensions

[Steffen Nurpmeso]

Markus Scherer <markus.icu at gmail.com> wrote:
 |I strongly recommend you parse the derived properties rather than trying to
 |follow the derivation formula, because that can change over time.

..this file includes only those core properties that have
themselves a derivation-may-change property?
(I long hesitated to write this though.)

--steffen