Check for duplicate files and other common issues.

Remove the vp10 directory to avoid having a whole ton of unused files.

--ignore-unmatch when using git rm so the script doesn't crash and exit
early.

Clarify why the scripts are upgraded to executable.

Search for files duplicated between vpx_dsp, vp8, and vp9 and warn. In
most cases this will cause build failures because currently none of the
build systems (including upstream) handle this case well.

R=tomfinegan@chromium.org

Review URL: https://codereview.chromium.org/1295663003 .
1 file changed