Move build config table to separate files.

Move the build configuration table into separate files.  The Configurations
file is standard configs, and Configurations.team is for openssl-team
members.  Any other file, Configurations*, found in the same directory
as the Configure script, is loaded.

To add another file, use --config=FILE flags (which should probably be
an absolute path).

Written by Stefen Eissing <stefan.eissing@greenbytes.de> and Rich Salz
<rsalz@openssl.org>, contributed by Akamai Technologies.

Reviewed-by: Richard Levitte <levitte@openssl.org>