Technical Team/Use Cases/2.0/Committer annotates source files with SPDX data

1. Title: Committer annotates source files with SPDX data
2. Primary Actor: Committer
3. Goal in Context: To indicate SPDX data for the file in the source code file.
4. Preconditions: 
   1. Committer has decided the license for the file they are committing
5. Stakeholders and Interests: 
   1. Committer: 
      1. To communicate the license information for the file in line with the file.
   2. Upstream maintainers: 
      1. To be able to have the source code be self documenting in a machine and human readable manner with respect to license information.
      2. To communicate the licensing information for their copyrightable artifacts.  
      3. To have their licenses respected
   3. Consumers of upstream source:
      1. To receive accurate and clear information of licensing of upstream source
      2. To be able to comply easily with licenses for upstream source
      3. To be able to subset, extend, or aggregate artifacts and pass on clear authoritative verifiable license for the resulting new copyrightable artifacts.
6. Main Success Senario: Source code files contain complete accurate SPDX data sufficient to communicate their licensing information in a way that is both human and machine readable.
7. Failed End Condition: Source code files lack complete accurate SPDX data.
8. Trigger:
   1. Commit of code to an upstream project.
9. Notes: There may be sub-use cases here around the distinction between original authorship of a file and capturing in SPDX existing information about the file, either from existing file headers or from commit logs.