to go through and find/fix buffer overflows and such.

If not available, LDBM uses big mutex and BDB2 is disabled.
Should add BerkeleyDB version detection...

Insert reference to ITS webpage

and back-ldbm are preserved, they only use the up-cased DNs. back-passwd
uses the mixed-case DN. All others are using mixed-case DN, may need more
fixing.

Let oc_check_allowed grok things like userCertificate;binary
oc_check_required should be fixed too.

Let at_find find the AttributeType that matches a given AttributeDescription.
Useful to deal with things like userCertificate;binary.

Add missing paren.

build/openldap.m4 and configure.in