Commit summary length hints (warning at 50, error at 72)

**Is your feature request related to a problem? Please describe.**
The waning coloring on the commit message is quite restrictive. Especially when company want to tag some commits with the issue ID it resolve, if the commit is a `feat`ure, a `fix`, … or sometime the `[functionality]` impacted. Real world software (screen size, website view, …) are more tolerant on long sized summary. Learning materials I read are more permissive than this 50 char "rule", ex in https://cbea.ms/git-commit/#limit-50 they say:
> So shoot for 50 characters, but consider 72 the hard limit.

Even in the linux kernel some message may be very long https://stackoverflow.com/a/11993051.

**Describe the solution you'd like**
When writing the summary, a warning color (yellow/orange) appear at 50 glyph, this transform in an error (current red is good) wean reaching 72 glyphs.
I really like to have a warning when I arrive at 50, I see if I should rephrase it now or not. When reaching 72 I take a bit more time to shorten my summary (and sometimes expand the body).

**Describe alternatives you've considered**
Keeping things as is since the real message is not limited in size. Or having configurable values.