Add a script that lists all contributors to a release (#1181)

* Add a script that lists all contributors to a release

We will keep a contributors database (simple JSON file) where
each entry is a contributor (either a committer, either an issue reporter,
either both) with some nicknames (GitHub, and Twitter).
The file will be used to craft credits on our release blog posts and to ping
them on Twitter.

* Add templates

* Missing docstring

* Clean-up

* Tweak

docs/contributors/generate.py

@@ -0,0 +1,41 @@
+"""
+Generate snippets to copy-paste.
+"""
+import sys
+
+from jinja2 import Template
+
+from fetch import HERE, load_awesome_people
+
+TPL_FILE = HERE / 'snippet.jinja2'
+HTTPIE_TEAM = {'jakubroztocil', 'BoboTiG', 'claudiatd'}
+
+
+def generate_snippets(release: str) -> str:
+    people = load_awesome_people()
+    contributors = {
+        name: details
+        for name, details in people.items()
+        if details['github'] not in HTTPIE_TEAM
+        and (release in details['committed'] or release in details['reported'])
+    }
+
+    template = Template(source=TPL_FILE.read_text(encoding='utf-8'))
+    output = template.render(contributors=contributors, release=release)
+    print(output)
+    return 0
+
+
+if __name__ == '__main__':
+    ret = 1
+    try:
+        ret = generate_snippets(sys.argv[1])
+    except (IndexError, TypeError):
+        ret = 2
+        print(f'''
+Generate snippets for contributors to a release.
+
+Usage:
+    python {sys.argv[0]} {sys.argv[0]} <RELEASE>
+''')
+    sys.exit(ret)