around the icc bug exhibited by buildfarm member dugong.

a minor markup improvement.

left to made, but this is a start.

where possible, add overview and incompatibilities lists, minor cleanups.
The SGML-ification still leaves much to be desired.

names.  ITAGAKI Takahiro

documentation.  Heikki and Tom

machines about casts between pointers and integers of different sizes.
While they're harmless, we shouldn't expect users to have to go through
and figure that out for themselves.

variable warning on Windows, improve comment.

trying BIO functions.
Helps problem with older versions of OpenSSL that lacks error
stack functions and would show an incorrect error message for
file-not-found-or-not-openable. The problem may still exist for
other errors, but file open error is by far the most common one.

Set pgtypes library version to 3.0.
Set compat library version to 3.0.

we restricted exports from ecpglib.

on MSVC.

Fix strange nonstandard version of __stdcall specifyer in thread
tests on win32.

Created export list for ecpglib.

the 'overview' and 'incompatibilities' summary lists remain to be
written.  But I think all the raw info is there (indeed maybe too
verbose).

make sure that a CPU option is actually chosen.

Hiroshi Saito

descriptor handling

OpenSSL libraries --- just don't call them if they're not there.  This
might possibly lead to misleading error messages, but we'll just have
to live with that.

This fixes potential crashes on old versions of OpenSSL and the requirement on
"Applink" in new versions when building with MSVC and using different
runtimes.

Dave Page with fixes from me.