Add masquerade utility function that allows a user to make API calls on behalf of another user.  Added tests.
Minor PEP-8 format fix.
Merge branch 'develop' into feature/masquerade

Conflicts:
	canvas_sdk/utils.py
	tests/test_utils.py
Merge branch 'develop' into feature/masquerade
Merge pull request #19 from Harvard-University-iCommons/feature/masquerade

Add masquerade utility function that allows a user to make API calls on ...