Feature/first release

W samym kodzie nic się nie zmienia oprócz namespace i interfejsu HttpClientOptions - przeniosłem go z PlatformOptions

changelog.txt

-= 1.7.0 - 2019-01-16 =
-* Changed public methods -> protected in ShipmentResponse
-* Changed shipment cost to be nullable
-
-= 1.6.5 - 2019-01-04 =
-* Added messageStock to rate response
-
-= 1.6.4 - 2018-12-18 =
-* Added label file extension
-
-= 1.6.3 - 2018-12-10 =
-* Added support for domain not allowed response code: 462
-
-= 1.6.2 - 2018-12-06 =
-* Added support for platform version hash in response headers
-
-= 1.6 - 2018-12-06 =
-* Added default request headers
+= 1.0 - 2019-01-31 =
+* First release