Tell the full report what libraries to get vaf info for

This way they will all have the same columns even if some have no
variants with coverage for a particular library.  This makes the
hacky "split columns" step during the merge unnecessary
More efficient library lookup
Update expected test data that was missed before
Need to return an array ref
Merge pull request #283 from apregier/fix_per_library_merge_problem

Tell the full report what libraries to get vaf info for