Drop .Net Standard 1.3 support

Release v0.8.10

Update NuGet API keys

bump v0.8.0

Bump to v0.7.2

Properly decode options with length between 13 and 269 bytes

Release 0.7.0

Add CancellationToken argument to ICoapTransport Async methods

Fixes #12

Perform a stable sort on CoapMessage.Options

Fixes #11

Merge branch 'malachi-iot-netstandard13'