test_nicks.csv and nicks.csv is overwritten during test execution

[zxiiro]

The files test_nicks.csv and nicks.csv are overwritten during test execution. Proper unittests should not modify the user's environment. Would recommend using something like tempfile [1] to create temporary files for testing.

Steps to reproduce:

1. touch nicks.csv
2. modify test_nicks.csv
3. python -m unittest test_bot
4. test_nicks.csv and nicks.csv is overwritten with test data

[1] https://docs.python.org/2/library/tempfile.html