v1.2.3: Fix time slot issue

Fixes an issue with custom time slot selection throught the timeSlotId of the shipment announcement model.

v1.2.2: Base-64 encoding for labels added

Added a new function on the Label class to retrieve the label data as base64 encoded data.

v1.2.1: Fixes small problems in stric environment

• Fixes #13 in a strict environment
• Fixes optional property problem where the properties needed to be supplied by the API

v1.2.0: Introduced label endpoints

• Introduces label endpoints
• Fixes multiple issues with the Guzzle client

v1.1.3: Fixes an issue with incorrect base url

• Fixes #9: The use of an incorrect base url.

V1.1.2: Fixes a problem with the base url

Fixes #9: A problem with the base url where a wrong path post-fix had been defined.

v1.1.1: Fix deprecation issue in Guzzle client

Fixes #7: The use of a deprecated Guzzle feature.

v1.1.0: Add new methods for better webhook support

Feature: Webhook implementation overhaul (#6)

* Feature: Webhook implementation overhaul

* Bump: v1.1.0