Issue 5250 - Add copyright update script

update-copyright/README.md

+# update-copyright
+
+This script accepts a URL to a mercurial index as input. It then:
+* makes a local copy of each repo
+* updates the copyright information on every file to the current year
+* attempts to push the updates
+
+If a user doesn't have permission to push to a repo, the script will make a local `repo-name.patch` file to submit later. 

[Sebastian Noack, 2017/07/05 18:55:21]

We always wrap code before 80 characters. While technically, this isn't code
here, the same reasoning applies, i.e. avoiding vertical scrolling and improving
the reading flow when looking at the raw text.

[rosie, 2017/07/07 15:55:47]

Done.

[rosie, 2017/07/07 16:44:00]

There are three places where the raw text is over 80 characters in the new
patch. Two are links that would otherwise be less than 80 characters. The third
is an example command. Are these ok, or should they also be wrapped?

[Sebastian Noack, 2017/07/07 16:58:29]

I guess that is fine.

[rosie, 2017/07/17 10:10:06]

Done.

+
+You are free to use this for other projects but please keep in mind that we make no stability guarantees whatsoever and might change functionality any time.
+
+## How to use
+
+To update the copyright on all the repos indexed at [https://hg.adblockplus.org/](https://hg.adblockplus.org/), you can use the accompanying shell script, e.g.:
+
+    ./run_update_copyright.sh
+
+To run the script elsewhere, you must specify the URL for a Mercurial index site to scrape, e.g.:
+
+    python3 update_copyright.py -u https://hg.example.com/
+
+You may also specify a base URL of a remote repo to push to, if it is different than the base URL of the index page, e.g.:
+
+    python3 update_copyright.py -u https://hg.example.com/ -p ssh://user@hg.example.com/
+
+## Testing
+
+Testing can be run via [tox](http://tox.readthedocs.org/).