Update runscript.py

Using the Python3.4 importlib method - Fails with imp module.
Updated runscript command to show script errors

The import command silenced all errors even if the fil existed.
Now, if the error is different from a non-existing file, the error is printed to help debug in case the verbosity is high enough.
Update runscript.py
Merge pull request #556 from achedeuzot/master

Update runscript.py to work on Python 3.4 withouyt __init__.py files