Merge bitcoin/bitcoin#34119: contrib: remove copyright_header.py

ba6315d contrib: remove copyright_header.py (fanquake)
3e4765e scripted-diff: [doc] Unify stale copyright headers (fanquake)

Pull request description:

  After #34084, our copyright headers shouldn't need "managing"; so remove the Python script.

ACKs for top commit:
  fjahr:
    ACK ba6315d
  rkrux:
    crACK [ba6315d](bitcoin/bitcoin@ba6315d)
  janb84:
    ACK ba6315d

Tree-SHA512: c0d6ed0a71803c5ae6c70260fa4162bea1f1b24cf6fc9b58e018bb9d6a673d2d59c25a17deda067a268024e3757081e3a214680e1e626d71c0debc5066d5f623

Author: glozow

contrib/devtools/README.md

@@ -61,65 +61,6 @@ the script should be called from the git root folder as follows.
 git diff -U0 HEAD~1.. | ./contrib/devtools/clang-format-diff.py -p1 -i -v
 ```
 
-copyright\_header.py
-====================
-
-Provides utilities for managing copyright headers of `The Bitcoin Core
-developers` in repository source files. It has three subcommands:
-
-```
-$ ./copyright_header.py report <base_directory> [verbose]
-$ ./copyright_header.py update <base_directory>
-$ ./copyright_header.py insert <file>
-```
-Running these subcommands without arguments displays a usage string.
-
-copyright\_header.py report \<base\_directory\> [verbose]
----------------------------------------------------------
-
-Produces a report of all copyright header notices found inside the source files
-of a repository. Useful to quickly visualize the state of the headers.
-Specifying `verbose` will list the full filenames of files of each category.
-
-copyright\_header.py update \<base\_directory\> [verbose]
----------------------------------------------------------
-Updates all the copyright headers of `The Bitcoin Core developers` which were
-changed in a year more recent than is listed. For example:
-```
-// Copyright (c) <firstYear>-<lastYear> The Bitcoin Core developers
-```
-will be updated to:
-```
-// Copyright (c) <firstYear>-<lastModifiedYear> The Bitcoin Core developers
-```
-where `<lastModifiedYear>` is obtained from the `git log` history.
-
-This subcommand also handles copyright headers that have only a single year. In
-those cases:
-```
-// Copyright (c) <year> The Bitcoin Core developers
-```
-will be updated to:
-```
-// Copyright (c) <year>-<lastModifiedYear> The Bitcoin Core developers
-```
-where the update is appropriate.
-
-copyright\_header.py insert \<file\>
-------------------------------------
-Inserts a copyright header for `The Bitcoin Core developers` at the top of the
-file in either Python or C++ style as determined by the file extension. If the
-file is a Python file and it has  `#!` starting the first line, the header is
-inserted in the line below it.
-
-The copyright dates will be set to be `<year_introduced>-<current_year>` where
-`<year_introduced>` is according to the `git log` history. If
-`<year_introduced>` is equal to `<current_year>`, it will be set as a single
-year rather than two hyphenated years.
-
-If the file already has a copyright for `The Bitcoin Core developers`, the
-script will exit.
-
 gen-manpages.py
 ===============