My copy and paste job was a little too much copy and I missed to adjust
it properly to sys/xattr.h all over and this is a fix to cure that.

CURLOPT_RESOLVE is a new option that sends along a curl_slist with
name:port:address sets that will populate the DNS cache with entries so
that request can be "fooled" to use another host than what otherwise
would've been used. Previously we've encouraged the use of Host: for
that when dealing with HTTP, but this new feature has the added bonus
that it allows the name from the URL to be used for TLS SNI and server
certificate name checks as well.

This is a first change. Surely more will follow to make it decent.

Removed the code that was needed for libcurl before 7.19.0 which now is
more than two years old.

Simplified the top comment and corrected the URL.

If the query result has a binary attribute, the binary attribute is
base64 encoded. But all following non binary attributes are also base64
encoded which is wrong.

This is a test (LDAP server is public).

curl
ldap://x500.bund.de:389/o=Bund,c=DE?userCertificate,certificateSerialNumber?sub
?cn=*Woehleke*

setxattr is a glibc call to set extended attributes, so configure now
checks for it and the code is adapted to only build when the
functionality is present.

It is often convinient to track back the source of a once downloaded
file; this patch makes curl store the source URL and other metadata
alongside the retrieved file by using the extended attributes (if
supported by the file system and enabled by --xattr).

Test 580 is removed again for two reasons:

1) Some compilers aren't satisfied by just a data variable called 'test'
when first.o wants a function called 'test'. The Solaris compiler says
"ld: warning: symbol `test' has differing types:" while the AIX compiler
downright rejects it.

2) Test case 1119 that was added after this test is way more complete
and cover everything test 580 does and more without introducing the same
problems.

This reverts commit b0fd03f5,
4b2fbe1e, afecd1aa, 68cde058

262 - Manual setting of TLS Server Name Indication - use Host:

If you use a custom Host: name in a request to a SSL server, libcurl
will now use that given name when it verifies the server certificate to
be correct rather than using the host name used in the actual URL.

The redirect check is already done at the position where the customhost
field is assigned so there's no point in doing that a second time.

When given a custom host name in a Host: header, we can use it for
several different purposes other than just cookies, so we rename it and
use it for SSL SNI etc.

OpenSSL SNI host name should be set to the custom Host header, if the
user provided one.

I've made the code intended using curl-style now to look more like other
examples.

My previous "fix" was a bit too invasive but is now fixed again.

An example application source code sending SMTP mail with the multi
interface. It is based on the code Alona Rossen provided, which in turn
is based on existing example/test code, and I converted it even more
into a decent example with a fair multi API use, put the info required
to edit at the top and I added some comments.

If a command is set type="perl", it can now specify a perl program that will
be run instead of an ordinary curl or built tool.

A perl test automatically disables memory and valgrind debugging.

This new script scans for all enums and #defines used by the curl/curl.h
and curl/multi.h headers. Then it reads all symbols mentioned in
symbols-in-vesions and make sure that there's no entries missing in
there. It then proceeds to verify that the entries that
symbols-in-vesions mentions but aren't found in the sources are truly
documented as removed.

This script is used in the new test case 1119

I've developed a script I call symbol-scan.pl that scans the curl.h and
multi.h header files and compare the symbols it finds in there with the
symbols symbols-in-versions documents and outputs a report on the
differences.  Using this I've dug through the history to fill up
symbols-in-versions with all the symbols my script found mismatches for.

I will commit symbol-scan.pl separatly and think of a way to put it to
use in the build/tests so that we from now on will get this in-sync
check automatically.

The new perl script mk580.pl generates a C table in a fresh source file
named lib580.c and if that compiles fine we know that the file
docs/libcurl/symbols-in-versions at least doesn't include any symbols
that are misspelled.

An additional feature would be to somehow scan curl/curl.h and compare
with symbols-in-versions to see if there are symbols missing.

Some FTP servers (e.g. Pure-ftpd) end up hanging if we close the data
connection before transferring all the requested data.  If we send ABOR
in that case, it prevents the server from hanging.

Bug: https://bugzilla.redhat.com/643656
Reported by: Pasi Karkkainen, Patrick Monnerat

These haven't worked in at least 8 years due to missing source
files, and most active RiscOS developers these days apparently
cross-compile anyway.

Signed-off-by: James Bursa <james@zamez.org>

Also, added a few hints to help compilers to perform tail call
recursion optimization.