Tartufo toml config validation

[rmarkins-godaddy]

Feature Request

Is your feature request related to a problem? Please describe.

tartufo should do some form of tartufo.toml validation. I ran into an issue where the excluded-signatures were not being read properly because it was below a [[tool.tartufo.exclude-entropy-patterns]]. Once I moved it above those only was it able to be read properly. Now this may just be how toml the language works and that is fine, but I am not a toml aficionado.

Describe the solution you'd like

If anything it would be helpful to either have some form of toml validation or documentation pointing on proper toml configuration for tartufo.