add support for platform artifacts

[MartinWitt]

Here we collect the information about the problems with plattform artifacts:

According to Stackoverflow we could define with https://stackoverflow.com/questions/6762271/how-to-use-platform-architecture-in-maven-to-determine-dependency that we assume we are the given arch for the lockfile

[monperrus]

We will add the platform metadata if the dependency is platform dependent

[monperrus]

fail if integrity checking is done on a different platform

platform is defined by OS and processor.

• documented in the README