Allow hash-prefix in color codes

[armsnyder]

The upstream gitlab-label-sync package supports the hash-prefix when it is run as a binary, but not as a library.

Could you detect and strip the # prefix while parsing config? It allows us to visualize colors with IDE plugins.

[EndBug]

@all-contributors please add @armsnyder for their code contribution

[allcontributors]

@EndBug

I've put up a pull request to add @armsnyder! 🎉