Handling missing 'people' key and error messages in API response

[MattSilverio]

Scenario:

ghunt email example@gmail.com

...

peoplepa.py", line 120, in people_lookup
person_data = list(data["people"].values())[0]
~~~~^^^^^^^^^^
KeyError: 'people'

Now:
[-] Request Error: {messages}

[munzzyy]

Every other API wrapper in the repo guards this. drive.py checks if "error" in data in all three of its methods, and clientauthconfig, identitytoolkit, geolocation, calendar and mobilesdk do the same. peoplepa's two methods have none, so this closes a real gap.

people() at line 206 on your branch, 199 on master, parses data["personResponse"][0]["status"] with no guard above it. So ghunt gaia still dies with KeyError: 'personResponse' on the same body Nem0oo posted in #513. Would you extend the check there too?

Two smaller things: import pprint on line 12 is unused, and the fallback string "Erro desconhecido." is Portuguese.