1. rnd_reference was a duplication of the work the the engine
framework does, and wasn't ever checked. Removed.
2. use the NO_ macros to disable appropriate algorithms.
3. Only implement the RNG stuff if AEPRAND is defined (default: not
defined, because the AEP people plan on having boards without it.
I'll see if I can device a more dynamic way of disabling this).
4. aep_finish() now closes all connections, and if that worked, does a
proper finalize.
5. proper AEP types are used to conform to the AEP definitions of
their own functions.
6. remake the use of thread locks. The use of CRYPTO_LOCK_DYNLOCK was
definitely inappropriate, and for random generator stuff, it's
better to use CRYPTO_LOCK_RAND.
Also, I applied certain changes that were provided by the AEP people.
Among others, BN_CTX_new() is not used to initialise a BN context
(this was never done before, and may have made things slower or not
working at all.
