StructuredValue attributes support

With this release we added StructuredValue attribute type support and decoding these attributes to maps or structs.

v0.5.3 - Fix unsafe casting in entity attributes

This release add the pull request #9

It fixes the entity attributes retrieving, avoiding unsafe castings and panics.

v0.5.2: Merge pull request #7 from phoops/add-last-success-code-subscription-…

Added LastSuccessCode for SubscriptionNotification

v0.5.1 - Add support forr custom global headers in http requests

Merge pull request #6 from CDimonaco/feature/custom_headers_in_client…

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Add support for custom global headers

v0.5.0

Added support for GeoJSON attributes.