build: iojs -> nodejs of release-urlbase

PR-URL: https://github.com/nodejs/node/pull/3015
Reviewed-By: Rod Vagg <r@va.gg>
Reviewed-By: Sakthipriyan Vairamani <thechargingvolcano@gmail.com>
Reviewed-By: Roman Reiss <me@silverwind.io>

configure

@@ -205,7 +205,7 @@ parser.add_option('--release-urlbase',
     dest='release_urlbase',
     help='Provide a custom URL prefix for the `process.release` properties '
          '`sourceUrl` and `headersUrl`. When compiling a release build, this '
-         'will default to https://iojs.org/download/release/')
+         'will default to https://nodejs.org/download/release/')
 
 parser.add_option('--v8-options',
     action='store',