Remove `import sys`

To satisfy flake8, and not trigger the F401 error, it was necessary to remove `import sys`, since it was no longer being used. This error slipped through Travis-CI because @erigler-usgs  got impatient waiting for Travis-CI to complete for a very simple PR and merged it before all tests were complete. Lesson learned.

geomagio/algorithm/SqDistAlgorithm.py

@@ -18,7 +18,6 @@ from .Algorithm import Algorithm
 from .AlgorithmException import AlgorithmException
 import json
 import numpy as np
-import sys
 from obspy.core import Stream, UTCDateTime
 from scipy.optimize import fmin_l_bfgs_b