FEAT: prescribe ALL-CAPS type when commit includes breaking change

[apetro]

BREAKING CHANGE: requires type in ALL-CAPS when the commit includes a breaking change, whereas previously type would always be lowercase. Tools enforcing Conventional Commits as understood prior to this change may flag or fail to correctly parse commit messages indicating breaking changes under this version of the spec.

When a commit includes a breaking change, surely this is the most important thing to say about that commit. So lead with it. Indicating the breaking-change-ness of a commit it its header rather than just in its body and footer makes it easier to skim to, notice, and parse out (from abbreviated representations of the commit log) these changes.

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This is another way of getting at the indicate-breaking-changes-in-the-header problem that #43 is trying to solve with a sigil. It might be that the sigil solution is better. I'm not sure that ALL-CAPS-ing the type: is the move to make here.

I do think something should be done to indicate the breakingness of changes in the header rather than only in the body or footer.

[apetro]

Note that #24 might make the spec agnostic as to capitalization of type, or might prescribe sentence-case, either way at odds with making the capitalization of type semantically meaningful.

[damianopetrungaro]

Hey @apetro!
As for the #64 please, open an issue before creating a PR trying to change the specs.
Here too I do not agree with the changes you proposed, see that imho it may create confusion and false positive.

Try to ping here -> #43 and let's see if it make sense add a sigil (or another way) to indicate BC in the message.