Hello!

I have the same problem as in Is there a way to prefix all sage code in order to include a custom module?, but the init.sage appears not to work with notebook's worksheet. Here is what I have:

```
$ cat ~/.sage/init.sage
import sys
import os
import numpy as np
dev_path = os.path.join(os.path.expanduser("~"), 'Development')
if dev_path not in sys.path:
sys.path.append(dev_path)
$ ~/Downloads/sage-6.10-Ubuntu_15.10-x86_64/sage
RecursionError: maximum recursion depth exceeded during compilation
┌────────────────────────────────────────────────────────────────────┐
│ SageMath Version 6.10, Release Date: 2015-12-18 │
│ Type "notebook()" for the browser-based notebook interface. │
│ Type "help()" for help. │
└────────────────────────────────────────────────────────────────────┘
sage: sys.path
sage: sys.path[-1:]
['/home/eugene/Development']
```

But then I run notebook(), create a new worksheet and the sys.path no longer contains additional line. I also have no numpy imported so I assume that **the script was not executed for the worksheet**.

Is there a way to create sage.init but for the worksheets?