Bring style closer to pep8

[JohnLZeller]

This library had many pep8 violations, and was using 2-space indents. This brings the code closer in line with pep8 styling, and uses 4-space indents, as it's the most common among Python packages.

I've run all unit tests and they pass with flying colors.

Two outstanding questions I have:

• In client.py, line 655
  • I've removed what seems to be an unused response variable. Do we want to return this value?
• In test_client.py, line 800
  • I've removed an unused client variable. Should something else be done with it here, that wasn't already happening?

I realize it's a lot of changes, but it's all styling. Let me know if you have any questions @maksim-s :)

[sds]

Thanks for this! Closing as at this time this contains a number of conflicts. Happy to merge a rebased PR!