Support exclude patterns

[rrousselGit]

Hello!

It appears that there are currently no way of excluding certain matches.
For example, a glob may want to match against foo.dart but reject foo_test.dart

The Glob syntax seems to support *[!_test].dart, but this does not appear to be supported by this package.

[vrnvorona]

same for !(pattern) globs. You can't really use library which calls itself glob but doesn't work like one, it's misleading.

[hyiso]

Same problem when using package lint_staged which use glob to match patterns

[erick-ciudaz]

with the same problem

[ManuelRauber]

Jepp. Same with generated files like a.dart and a.g.dart. I want to format a.dart but leave a.g.dart as it was generated.

[takumma]

I think you can use ! and ^ like *[!_test].dart or **[^.g].dart.

I found the following in the README, and also saw such an implementation in the code :)

If it starts with ^ or !, the construction will instead match all characters not mentioned. For example, test[^a-z].dart will match test1.dart but not testa.dart.