Adds in a new TimedClient() class.

This new subclass of Client() allows you to time each call to the API.
Adding some documentation
Adding in --timings flag to the CLI to use the new TimedClient
Removing unnecessary changes
Adding in timestamp of when each API call was initiated
Fixing unit tests and slight code refactoring
Adding missing asterisk that was preventing calls with arguments from working
Converting timestamp to UTC
Merge pull request #174 from beittenc/api_timing

Create new TimedClient class