Second patch release:

_ In case an ldap library is not found at configure time, a warning is
issued and LDAP compilation is disabled.
_ The whole C code is based on header file structures and prototypes,
and some new preprocessor definitions.
_ lib/ldap.h has been renamed lib/curl_ldap.h

Compiles and run successfully on cygwin and FC6.

Specific config-* and Makefile.* have been checked (and) carefully, but
a test is desirable. Especially for tpf platform, that seems to use
LDAP, but without any additional info. I suppose it should be disabled
for this platform...

Try it !

Patrick