trouble if header files are included in some "impropper" order.
It's much better if the application programmer has to specify on his
or her own if _REENTRANT shall be defined and when.

Add PBE algorithms with ciphers, not digests.

Allow ADH to be used but not present in the default cipher
list.

Allow CERTIFICATE to be used in PEM headers for PKCS#7 structures:
some CAs do this.

Make EVP_CIPHER_type() return NID_undef if the cipher has no
ASN1 OID, modify code to handle this.

library, the output buffer always is large enough, but if the tlen
parameter is there, it should be checked in the interest of clarity,
as proposed by David Sacerdote <das33@cornell.edu>.

the old functionality.

Various warning fixes.

Initial EVP symmetric cipher docs.

ssl3_get_message, which is more logical (and avoids a bug,
in addition to the one that I introduced yesterday :-)
and makes Microsoft "fast SGC" less special.
MS SGC should still work now without an extra state of its own
(it goes directly to SSL3_ST_SR_CLNT_HELLO_C, which is the usual state
for reading the body of a Client Hello message), however this should
be tested to make sure, and I don't have a MS SGC client.

designed for that.  This removes the potential error to mix data and
function pointers.

Please note that I'm a little unsure how incorrect calls to the old
ctrl functions should be handled, in som cases.  I currently return 0
and that's it, but it may be more correct to generate a genuine error
in those cases.