Find node path using shell/which.
Find node path using shell/which.

Without this patch, Make would fail with the following error:

```
> make
/bin/sh: node: command not found
make: *** [node_modules] Error 127
```
This may be something strange about my computer's configuration, but
seems like a harmless change.

jabaz/debug,zacronos/debug,CantemoInternal/debug,jabaz/debug,visionmedia/debug,elliottsj/debug,CantemoInternal/debug,zacronos/debug,elliottsj/debug