Assign a name to your Tamagotchi

[rafaelhenrique]

Based on class described here:
https://groups.google.com/forum/#!topic/python-sorocaba/w2EvUun-NHQ

• Give an Name to Tamagotchi via POST if Tamagotchi have a name then change the name via PUT

[rafaelhenrique]

One PR for this issue is only accepted if have tests and Coverage > 90%.