The more proper place for shell scripts dedicated for development, and
releasing PHP should be the scripts/dev directory. Having a cleaner root
project directory helps find the main README.md and files relevant to
install PHP.

These scripts are also used by the release managers mostly who create
release packages and aren't used often by the majority of developers
working on and installing PHP.

The --copy option was once used with Automake. It has been
removed via 128119b9abf3446b3867ed6d6bf1503a54bf45ea.

The Autoconf macro AC_CONFIG_AUX_DIR can set the location of the
auxiliary build tools such as config.guess, config.sub, and bundled
libtool scripts and moves these bundled files from the root directory
to the build subdirectory.

Additionally some changes in this context or as a part of obsoletion:
- The LT_TARGETS variable in build/build2.mk file was once used as a part
  of the Automake step. It's not used anymore and has been refactored to
  separate makedist script directly.
- ltconfig is not used anymore since libtool 1.4+
  cf8d1563c27a70fdd24055c1e80218ec7b5962d6
- phpize file locations for the config.guess, config.sub, and ltmain.sh
  has been refactored accordingly.

* PHP-7.2:
  [ci skip] Update NEWS
  [ci skip] Update NEWS
  Fix #77041: buildconf should output error messages to stderr

* PHP-7.1:
  [ci skip] Update NEWS
  Fix #77041: buildconf should output error messages to stderr

Since PHP 5.3 flex lexer has been replaced with re2c. Commit
0f9e2b1753661afe1c0dee6982e161fcf00d349f made PHP_PROG_LEX macro still
available for BC.

In commit df6bd506d492292ef4353b0f8da0c34eeb076be5 it was updated. Since
this macro is entirely not used in PHP source code anymore from PHP 5.3
and up, this patch removes it together with some old traces of warnings
suppression and comments.