remove --with-maxminddb;
  maxminddb libs not currently part of our FreeBSD build images

(reduce string copying)

split out func mod_alias_remap() from handler func for unit testing

avoid multiple definition of SHA512_CTX when using Nettle

use different vars for different crypto libs

remove --with-mbedtls; mbedlts not currently part of our FreeBSD bld img

remove --with-nss; nss libs not currently part of our FreeBSD build img
remove with_zstd=yes from SCons build, due to dependency on libpthread

WolfSSL is not generally available in *BSD due to WolfSSL limitations.
(Might be revisited with the Dec 2020 release of WolfSSL 4.6.0)

* remove use of deprecated or obsolete packages on Linux, *BSD builds
  --with-attr --with-fam --with-geoip
* add zstd
  --with-zstd
* add multiple TLS options to build
  --with-gnutls --with-mbedtls --with-nss --with-openssl --with-wolfssl
  (leave one TLS option (openssl) for SCons static build)

(quiet compiler warning)

use fdopendir(), fstatat(), if available

set Ciphersuites once API is available (SSL_CTX_set_ciphersuites())
in LibreSSL.

x-ref:
  "Add support for TLS 1.3"
  https://github.com/libressl-portable/portable/issues/228

fix typo: honor user-defined CipherString for alternative TLS libraries
(LibreSSL, BoringSSL, wolfSSL)

Do not issue trace if multiple */vnd.* register the same extension

(silently mark mime-type for extension as application/octet-stream)

(thx hamelg)

x-ref:
  "segfault with mod_scgi on backend server with unix socket domain"
  https://redmine.lighttpd.net/issues/3052

Do not issue warnings about duplicated entries unless called with -v

/etc/mime.types is not typically edited by the end user,
so the warning trace is noise to most end users.

make create-mime.conf.pl more resilient to questionable edits
to /etc/mime.types

non-vnd.* subtype takes precedence over vnd.* subtype
  (type/subtype, e.g. text/plain)

x-ref:
  "lighttpd: does not start with media-types 1.1.0"
  https://bugs.debian.org/cgi-bin/bugreport.cgi?bug=979232

buffer_is_equal_caseless_string() -> buffer_eq_icase_slen()

When known, use HTTP_HEADER_* enum before string comparisons

(thx glen)

Regression in lighttpd 1.4.56 - 1.4.58 when extforward.headers is
not set in lighttpd.conf.

Workaround: extforward.headers = ("X-Forwarded-For")
  (or appropriate value depending on header sent by upstream proxy)

x-ref:
  "mod_extforward regression 1.4.56"
  https://redmine.lighttpd.net/issues/3051

expand config warning for module load order to include other TLS modules

extend ssl.openssl.ssl-conf-cmd to accept "SecurityLevel"
(lighttpd extension) and use the (string) value to call the
openssl-specific SSL_CTX_set_security_level()

make create-mime.conf.pl more resilient to questionable edits
to /etc/mime.types

x-ref:
  "lighttpd: does not start with media-types 1.1.0"
  https://bugs.debian.org/cgi-bin/bugreport.cgi?bug=979232

avoid spurious test failures due to conflicts with ports in use by
other processes, which might occur when tests use hard-coded ports

If server.systemd-socket-activation = "enable" and one or more of the
sockets is not listed in lighttpd.conf, then when the server is shutting
down, a buffer from the config file is free()d twice.

update scripts/m4/ax_prog_cc_for_build.m4 from serial 8 to serial 18

https://www.gnu.org/software/autoconf-archive/ax_prog_cc_for_build.html
http://git.savannah.gnu.org/gitweb/?p=autoconf-archive.git;a=blob_plain;f=m4/ax_prog_cc_for_build.m4

autoupdate; subst deprecated/obsolete macros
- s/AC_HELP_STRING/AS_HELP_STRING/
- others

allocate memory for PATH_MAX to avoid pathconf() for _PC_NAME_MAX

On some older gcc, strncmp is a macro and expects three arguments,
but does not see expansion of lighttpd CONST_STR_LEN() macro before
warning/error about incorrect number of arguments

On some older gcc, strncmp is a macro and expects three arguments,
but does not see expansion of lighttpd CONST_STR_LEN() macro before
warning/error about incorrect number of arguments

include mbedtls/platform_util.h for mbedtls_platform_zeroize()
(instead of relying on an indirect include)

(fixes build with (very old) mbedtls-2.14.0)

hide unused funcs depending on build flags

read retry loop needs separate var for result and data size to read

rename 'toSend' variable to 'len' (of chunk)