License Handling

[AgentD]

At the moment it is pretty much ignored since this project only distributes the tooling and no pre-built images.

At some point, taking care of not violating any licenses becomes necesary.

What I think needs to be done:

• Add license string to every binary package (holding an SPDX expression) and whether it contains
  static libraries, dynamic libraries, headers, executables.
• Somehow mark packages that patch their source.
• Generate a report about packages that modify their source and have copyleft licenses or licenses that require modified versions to be marked.
• Check license compliance and what license to use when building packages that link against stuff from other packages.
• When building the rootfs package, determine what licenses we need from the package list and include them.
• Add an auto generated list to the rootfs with upstream package source locations and a reference to the license.
• Figure out how to handle modified, copyleft licensed packages.