add keep-only-pid-0 option to fb-fix-cmap script
add keep-only-pid-0 option to fb-fix-cmap script

And also bugfix the old features and improve this tool's output formatting.
(issue #1591)

graphicore/fontbakery,googlefonts/fontbakery,graphicore/fontbakery,moyogo/fontbakery,graphicore/fontbakery,googlefonts/fontbakery,moyogo/fontbakery,googlefonts/fontbakery,moyogo/fontbakery