105 - "invalid free after an http redirect to ftp"

https://bugzilla.novell.com/show_bug.cgi?id=332917 about a HTTP redirect to
FTP that caused memory havoc. His work together with my efforts created two
fixes:

#1 - FTP::file was moved to struct ftp_conn, because is has to be dealt with
     at connection cleanup, at which time the struct HandleData could be
     used by another connection.
     Also, the unused char *urlpath member is removed from struct FTP.

#2 - provide a Curl_reset_reqproto() function that frees
     data->reqdata.proto.* on connection setup if needed (that is if the
     SessionHandle was used by a different connection).

way:

93 - Digest for IIS fix (subject for removal)
100 - icc segmentation faults (subject for removal)

that specifying a proxy with a trailing slash didn't work (unless it also
contained a port number).

when assigning a NULL pointer to a function pointer var.

In CURL_CHECK_LIBS_WINLDAP and CURL_CHECK_LIBS_LDAP, check first with no
additional library even when the optional list of libraries has been given.

Specifically for linux x86-64 with Intel's icc.

icc warning level with libcurl's

may lose significant bits

failure condition: http://curl.haxx.se/mail/lib-2007-10/0152.html

when assigning a NULL pointer to a function pointer var.

and allow parameter specification of libraries to check.

Fix a bug where fallback from AF_INET6 to AF_INET would not work properly together with relative search; if you had a search path of .a.com and .b.com, and foo.a.com would return ARES_ENODATA and foo.b.com would return ARES_ENOTFOUND, the lookup would not properly retry with AF_INET as it forgot the first ARES_ENODATA.

Don't confuse NUL with NULL.

CURLOPT_COPYPOSTFIELDS option added for dynamic.
Fix some OS400 features.

Fixed a typo in the LDAP configure code and made sure NULL is defined
in a test programs that need it.