Don't run PYTHONSTARTUP file if a file or code is passed

This modifies Python so the behavior is how Python behaves, this is the current situation:

![](http://monosnap.com/image/PUfzRh2mFpjrQA59aMYs27aBh30Wc3.png)

The same happens when you pass code to the Python binary vs. the IPython binary.