0.1.9 Add 'update_or_create' method to Contact class

[oroth8]

This method allows the use of querying the Hubspot api via contact email.

• If a record is returned on initial query, then the hubspot contact record is updated with the passed body
• If a a record in not returned on initial query, then a contact record is created in hubspot with the passed body

The parse_response method was adjusted to handle 404 errors to raise a EasyHubspot::HubspotApiError

This PR contains specs for the feature and additional fixtures.