Add X-Locale interceptor to API

[paulsmelser]

Add an overload method to the Connection.getApi() that allows users to pass Locale. We will use the Locale passed to add the X-Locale header using an interceptor.

Note: this only works if we can pass the X-Locale to all endpoints.

e.g.

connection.getApi(Locale.CANADA_FRENCH); // Will return an API that always includes X-Locale = fr-CA allowing responses to be in french