Throws a missleading error a the module fails to load

Currently this module swallows all errors when the trying to load a module.

I suggest adding this to the catch block:

```
if(ex.code !== 'MODULE_NOT_FOUND') {
   throw ex;  
}
```

This allows the module to still search up the stack, but if it finds a module and has a legitimate error loading the module you can still catch that error.
