assert: typed array deepequal performance fix

assert.deepEqual: when actual and expected are typed arrays,
wrap them in a new Buffer each to increase performance
significantly.

PR-URL: https://github.com/nodejs/node/pull/4330
Fixes: https://github.com/nodejs/node/issues/4294


Reviewed-By: James M Snell <jasnell@gmail.com>
Reviewed-By: Matteo Collina <matteo.collina@gmail.com>
Reviewed-By: Roman Reiss <me@silverwind.io>
Reviewed-By: Colin Ihrig <cjihrig@gmail.com>