Improve scoring for added files

[steven-esser]

We should have some way to distinguish the importance of added files.

For instance, added files with license and/or copyright info should be scored higher than just plan fileinfo.

Also, if there is some sort of non-permissive licensing this should also increase the score.

[johnmhoran]

@MaJuRG When you have time, I can show you the buggy license_diff() and copyright_diff() behavior with the React codebase that I mentioned on yesterday's Slack call.

[johnmhoran]

@MaJuRG Do you have a preference between (1) addressing both added and modified in a single license diff (currently: determine_license_diff()) and (2) splitting the current method into separate methods for added and modified? (Similar question for copyright detection.)

[steven-esser]

If you can reliable handle added files in those functions, then that would probably be fine.

[johnmhoran]

@MaJuRG I think this issue is ready for a PR -- shall I . . . ?

[steven-esser]

sure

[steven-esser]

merged #92, closing.