Thanks folks:
        348 Benjamin Kaduk
        317 Christian Brueffer
        254 Erik Tews
        253 Erik Tews
        219 Carl Mehner
        155 (ghost)
        95 mancha
        51 DominikNeubauer
Reviewed-by: NDr. Stephen Henson <steve@openssl.org>

Signed-off-by: NRich Salz <rsalz@akamai.com>
Reviewed-by: NTim Hudson <tjh@openssl.org>

Submitted by: Tobias Stoeckmann <tobias@bugol.de>

prototypes, etc. Also, some fairly significant edits were made to the text
(who wrote this crap anyway? oh wait ...), removing stuff which is
overkill, rewriting stuff that was opaque, correcting things that were just
downright false, etc.

first-cut but provides better documentation than having nothing on the
ENGINE API.