HDTN Version 1.3.1

HDTN v1.3.0 Release

HDTN hotfix release v1.2.1

Change HdtnVersion.hpp to version 1.2.0

Merge branch 'development' into 'master'

HDTN release merge request

See merge request hdtn-v4/hdtn!286

Merge branch 'development' into 'master'

Development

See merge request hdtn-v4/hdtn!215