libeay.num got tweaked so the old des symbols would retain their
positions.

section.

Add ui_compat.h for inclusion by those who want the old functions and
provide all of them, not just the higher-level ones, in ui_compat.c.

like des_read_password and friends (backward compatibility functions
using this new API are provided).  The purpose is to remove prompting
functions from the DES code section as well as provide for prompting
through dialog boxes in a window system and the like.