Add test for pruning the generated README
Rename some test files to be more descriptive
v0.142250

    - If you pruned away the README(.*) file before it could be populated with
      content, you'd get a fatal error like " Can't call method "name" on an
      undefined value at ...". Now we detect this and throw a more helpful
      (but still fatal) error suggesting you check your PruneFiles
      config. RT #97976. (Dave Rolsky)