module: avoid ArgumentsAdaptorTrampoline frame

Avoid an unneeded ArgumentsAdaptorTrampoline stack frame by passing the
the right number of arguments to Module._load() in Module.require().
Shortens the following stack trace with one frame:

    LazyCompile:~Module.load module.js:345
    LazyCompile:Module._load module.js:282
    Builtin:ArgumentsAdaptorTrampoline
    LazyCompile:*Module.require module.js:361
    LazyCompile:*require internal/module.js:11

PR-URL: https://github.com/nodejs/node/pull/4575
Reviewed-By: Colin Ihrig <cjihrig@gmail.com>
Reviewed-By: James M Snell <jasnell@gmail.com>

lib/module.js

@@ -374,7 +374,7 @@ Module.prototype.load = function(filename) {
 Module.prototype.require = function(path) {
   assert(path, 'missing path');
   assert(typeof path === 'string', 'path must be a string');
-  return Module._load(path, this);
+  return Module._load(path, this, /* isMain */ false);
 };