VMS: Add installation verification procedure

On VMS, it's customary to have a procedure to check that the software
was installed correctly and can run as advertised.

The procedure added here is fairly simple, it checks that all
libraries are in place, that the header crypto.h is in place, and that
the command 'openssl version -a' runs without trouble.

Reviewed-by: Rich Salz <rsalz@openssl.org>