Add preliminary mailmap and tool to generate it

.mailmap

@@ -0,0 +1,18 @@
+K.-Michael Aye <michaelaye@users.noreply.github.com> <kmichael.aye@gmail.com>
+Nelson Brown <nelson.brown@gmail.com> <nelson.a.brown@nasa.gov>
+Luis Pedro Coelho <luis@luispedro.org> <lpc@cmu.edu>
+Marianne Corvellec <marianne.corvellec@ens-lyon.org> <mcorvellec@april.org>
+Riaan van den Dool <riaanvddool@gmail.com> <rvddool@csir.co.za>
+Emmanuelle Gouillart <emmanuelle.gouillart@normalesup.org> <emma@aleph.(none)> <gouillar@epsilon.(none)> <emmanuelle.gouillart@nsup.org> <gouillar@aleph.(none)>
+Thouis (Ray) Jones <thouis@gmail.com> <thouis@seas.harvard.edu>
+Gregory R. Lee <gregory.lee@cchmc.org> <grlee77@gmail.com>
+Andreas Mueller <amueller@ais.uni-bonn.de> <andreas@wuerl.net>
+Juan Nunez-Iglesias <juan.n@unimelb.edu.au> <jni.soma@gmail.com> <jni@janelia.hhmi.org>
+Nicolas Pinto <pinto@alum.mit.edu> <nicolas.pinto@gmail.com>
+Johannes Schönberger <jsch@demuc.de> <ahojnnes@users.noreply.github.com> <hannesschoenberger@gmail.com> <jschoenberger@demuc.de>
+Tim Sheerman-Chase <tim2009@sheerman-chase.org.uk> <t.sheerman-chase@surrey.ac.uk>
+Matthew Trentacoste <trentaco@adobe.com> <web@matttrent.com>
+James Turner <jturner@gemini.edu> <jehturner@yahoo.co.uk>
+Stefan van der Walt <stefanv@berkeley.edu> <stefan@sun.ac.za> <github@mentat.za.net> <sjvdwalt@gmail.com>
+John Wiggins <jwiggins@enthought.com> <john.wiggins@xfel.eu>
+Tony S Yu <tyu@tony-yus-macbook.local> <tsyu80@gmail.com>

tools/mailmap.py

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+#!/usr/bin/env python
+# Requires package 'editdistance'
+
+# A mailmap file is used (by GitHub and other tools) to associate multiple
+# commit emails with one user.  This helps to count number of commits,
+# contributors, etc.
+
+import subprocess
+import shlex
+import numpy as np
+from collections import defaultdict
+
+from editdistance import eval as dist
+
+threshold = 5
+
+def call(cmd):
+    return subprocess.check_output(shlex.split(cmd), universal_newlines=True).split('\n')
+
+
+def _clean_email(email):
+    if not '@' in email:
+        return
+
+    name, domain = email.split('@')
+    name = name.split('+', 1)[0]
+
+    return '{}@{}'.format(name, domain).lower()
+
+
+call("rm -f .mailmap")
+authors = call("git log --format='%aN::%aE'")
+
+names, emails = [], []
+
+for (name, email) in (author.split('::') for author in authors if author.strip()):
+    if email not in emails:
+        names.append(name)
+        emails.append(email)
+
+N = len(names)
+D = np.zeros((N, N)) + np.infty
+
+for i in range(1, N):
+    for j in range(i):
+        D[i, j] = dist(names[i], names[j])
+
+for i in range(N):
+    dupes, = np.where(D[:, i] < threshold)
+    for j in dupes:
+        names[j] = names[i]
+
+mailmap = defaultdict(set)
+for (name, email) in zip(names, emails):
+    email = _clean_email(email)
+    if email:
+        mailmap[name].add(email)
+
+for key, value in list(mailmap.items()):
+    if len(value) < 2 or (len(key.split()) < 2):
+        mailmap.pop(key)
+
+entries = []
+for name, emails in mailmap.items():
+    entries.append([name])
+    entries[-1].extend(['<{}>'.format(email) for email in emails])
+
+entries = sorted(entries, key=lambda x: x[0].split()[-1])
+for entry in entries:
+    print(' '.join(entry))