Add `prioritize_line_class_coverage` option

[trsxxii]

Hi @Malinskiy

Added an option to prioritize LINE (C0) coverage output for each class. This is because even though the total coverage always outputs C0 coverage, the per-class coverage was prioritizing C1 if C1 was available. This would cause inconsistency, so the option to output C0 coverage was necessary.

The default behavior has been made the same as before, so there is no need for users to do anything after the upgrade. Users only need to set this option if they need it.

Thank you.

[Malinskiy]

Hey @trsxxii

Thanks for the PR.

Upon review I think it makes sense to have both options: prioritise branch/line coverage. Would you be able rework this to support an enum of sorts to select branch vs line?

Thanks much!

FYI: Travis is removed from the repo, I suggest merging with latest master to have the GitHub Actions config applied properly

[aiKrice]

up @trsxxii