GeneralizedTime. At several points PKIX specifies that GeneralizedTime can be
used but OpenSSL doesn't currently support it. This patch adds several files
and a bunch of functions.

Of interest is the ASN1_TIME structure and its related functions. At several
points certificates, CRLs et al specify that a time can be expressed as a
choice of UTCTime and GeneralizedTime. Currently OpenSSL interprets this
(wrongly) as UTCTime because GeneralizedTime isn't supported. The ASN1_TIME
stuff provides this functionality.

Still todo is to trace which cert and CRL points need an ASN1_TIME and modify
the utilities appropriately and of course fix all the bugs.

Note new OpenSSL copyright in the new file a_time.c. I didn't put it in
a_gentm.c because it is a minimally modified form a_utctm.c .

Since this adds new files and error codes you will need to do a 'make errors'
at the top level to add the new codes.