Issue 5250 - Add copyright update script

update-copyright/README.md

 # update-copyright
 
-A script that opens each repo listed on [hg.adblockplus.org](https://hg.adblockplus.org/) and updates the copyrights on each page to the current year.
+This script will attempt to update the eyeo copyright information on each
+page of each repo listed on a Mercurial index page.
+By default, running the script will scrape [https://hg.adblockplus.org/](https://hg.adblockplus.org/),
+and then for each repo, it will:
+* make a local copy of the repo
+* update the copyright information on each file to the current year
+* attempt to push the updates to `ssh://hg@hg.adblockplus.org/`
 
-## Usage
+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. 
 
-Runs the deault script:
-    $ python3 update_copyright.py
+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.
 
-Specify which Mercurial URL site to scrape
-    $ python3 update_copyright.py -u https://hg.adblockplus.org/
+## How to use
 
-Specify which Mercurial URL site to scrape and which remote repo to push to
-    $ python3 update_copyright.py -u https://hg.adblockplus.org/ -p ssh://hg@hg.adblockplus.org/
+To update the copyright on all the repos indexed at [https://hg.adblockplus.org/](https://hg.adblockplus.org/),
+simply run the script, e.g.:
+
+    ./update_copyright.py
+
+To run the script elsewhere, you must specify the URL for a Mercurial index
+site to scrape, and the location of the base URL to push to, e.g.:
+
+    ./update_copyright.py -u https://hg.example.com/ -p ssh://user@hg.example.com/
 
 ## Testing
 
-The tests can be run via [Tox](http://tox.readthedocs.org/)
+Testing can be run via [tox](http://tox.readthedocs.org/).