* Travis CI: Add more flake8 tests
* Use ==/!= to compare str, bytes, and int literals
./project_euler/problem_17/sol1.py:25:7: F632 use ==/!= to compare str, bytes, and int literals
if i%100 is not 0:
^
* Use ==/!= to compare str, bytes, and int literals
* Update sol1.py