Simplify license headers

I think author's name on each file is good practice. Once i used this information.
IMHO the shortest header is the nicest one.On Jan 27, 2019 20:38, Nikita Popov nikita.ppv@gmail.com wrote:

Hi internals,

Some of our source files currently contain a license header similar to this:

/*
+----------------------------------------------------------------------+
| PHP Version 7 |
+----------------------------------------------------------------------+
| Copyright (c) 1997-2018 The PHP Group |
+----------------------------------------------------------------------+
| This source file is subject to version 3.01 of the PHP license, |
| that is bundled with this package in the file LICENSE, and is |
| available through the world-wide-web at the following url: |
| http://www.php.net/license/3_01.txt |
| If you did not receive a copy of the PHP license and are unable to |
| obtain it through the world-wide-web, please send a note to |
| license@php.net so we can mail you a copy immediately. |
+----------------------------------------------------------------------+
| Authors: Andi Gutmans andi@php.net |
| Zeev Suraski zeev@php.net |
+----------------------------------------------------------------------+
*/

I would like to make two changes to this header:

1. Change "PHP Version 7" line to just "PHP", to avoid the necessity of
   updating this for new major versions. I don't think the version information
   here is particularly useful to anybody.

2. Remove the "Copyright (c) 1997-2018 The PHP Group" line. Apart from
   requiring a yearly update, this line is actually complete misinformation,
   because the PHP group does not hold the copyright for the PHP source
   code. This would require a copyright assignment agreement on behalf of all
   contributors, which we do not collect.

We could also just drop the header entirely, I'm just proposing these two
changes as the path of least resistance towards getting the "annoying"
parts removed.

Regards,
Nikita