deps: upgrade npm to 2.7.4

Reviewed-By: Julien Gilli <julien.gilli@joyent.com>
PR-URL: #14180

deps/npm/.mailmap

@@ -1,5 +1,6 @@
 Arlo Breault <arlolra@gmail.com>
 Alex K. Wolfe <alexkwolfe@gmail.com>
+Andrew Bradley <cspotcode@gmail.com>
 Andrew Lunny <alunny@gmail.com>
 Benjamin Coe <bencoe@gmail.com>
 Brian White <mscdex@mscdex.net> <mscdex@gmail.com>
@@ -8,16 +9,19 @@ Dalmais Maxence <root@ip-10-195-202-5.ec2.internal>
 David Beitey <david@davidjb.com>
 Domenic Denicola <domenic@domenicdenicola.com>
 Einar Otto Stangvik <einaros@gmail.com>
-Evan Lucas <evan@btc.com> <evanlucas@me.com> <evan.lucas@hattiesburgclinic.com>
+Evan Lucas <evan@btc.com> <evanlucas@me.com>
+Evan Lucas <evan@btc.com> <evan.lucas@hattiesburgclinic.com>
 Faiq Raza <faiqrazarizvi@gmail.com>
 Forbes Lindesay <forbes@lindesay.co.uk>
-Forrest L. Norvell <forrest@npmjs.com> <ogd@aoaioxxysz.net>
+Forrest L Norvell <ogd@aoaioxxysz.net> <forrest@npmjs.com>
 Gabriel Barros <descartavel1@gmail.com>
 Geoff Flarity <geoff.flarity@gmail.com> <gflarity@raptvm-x02.(none)>
 Isaac Z. Schlueter <i@izs.me> <i@foohack.com>
+Isaac Z. Schlueter <i@izs.me> isaacs <i@izs.me>
 Jake Verbaten <raynos2@gmail.com>
 James Sanders <jimmyjazz14@gmail.com>
 Jason Smith <jhs@iriscouch.com>
+Jonas Weber <github@jonasw.de>
 Kris Windham <kriswindham@gmail.com>
 Lin Clark <lin.w.clark@gmail.com>
 Maciej Małecki <me@mmalecki.com> <maciej.malecki@notimplemented.org>
@@ -26,6 +30,9 @@ Maxim Bogushevich <boga1@mail.ru>
 Max Goodman <c@chromakode.com>
 Nicolas Morel <marsup@gmail.com>
 Olivier Melcher <olivier.melcher@gmail.com>
+Ryan Emery <seebees@gmail.com>
+Sam Mikes <smikes@cubane.com>
+Tony <zearin@gonk.net>
 Visnu Pitiyanuvath <visnupx@gmail.com>
 Will Elwood <w.elwood08@gmail.com>
-Zeke Sikelianos <zeke@sikelianos.com>
+Zeke Sikelianos <zeke@sikelianos.com>