Changed style in __init__.py module code.

I did change in __init__.py faitout package file. 

1 - Changed double "if else", for one "if else" with method "get" of the dict in Python.
2 - Removed double decorator @APP.route... Only route with trailing slash is enough. [0]
3 - Added final line in some files and removed double line in others file.

[0] https://flask.readthedocs.org/en/latest/api/#url-route-registrations