A handful of modules (including readable-streams) make
inappropriate use of the internal _events property. One
such use is to prepend an event listener to the front
of the array of listeners.
This adds EE.prototype.prependListener() and
EE.prototype.prependOnceListener() methods to add handlers
to the *front* of the listener array.
Doc update and test case is included.
Fixes: https://github.com/nodejs/node/issues/1817
PR-URL: https://github.com/nodejs/node/pull/6032
Reviewed-By: Сковорода Никита Андреевич <chalkerx@gmail.com>
Reviewed-By: Brian White <mscdex@mscdex.net>
