add shebang to app.py
add shebang to app.py

http://stackoverflow.com/questions/6908143/should-i-put-shebang-in-pytho
n-scripts-and-what-form-should-it-take

This partially satisfies
https://github.com/kristovatlas/osx-config-check/issues/84

kristovatlas/osx-config-check,kristovatlas/osx-config-check,kristovatlas/osx-config-check