Add file specific and project specific exceptions

[izmalk]

Implement a way to add project-wide and file-wide exceptions for Vale style checks.

For example:

 /home/izmalk/test/docs/izmalk/kafka-k8s-operator/docs/reference/r-statuses.md
 12:28  error    Did you really mean 'params'?   Vale.Spelling                          
 22:5   warning  Avoid the phrase 'Terminated'   Canonical.020-Cliche-words-and-phrases 

In the above output we see an error for the params which is a quote of the exact output produced by a program and a warning for the Terminated word, which is a name of a status and a correct technical term in this context.

I'd like to have a way to set project-specific and, ideally, file-specific exceptions for Vale checks.
File-specific exceptions are great for specific stuff that should not affect the whole project, like quotes of the output or status names.

[SecondSkoll]

This can be done in a few ways now. With Vale's inbuild comment delimiters, with the .custom-wordlist.txt file in a project's repository, and also by attaching specific classes to words. This is not fully detailed yet, you need to include role definitions in your project that define specific classes:

rst_prolog = """
.. role:: woke-ignore
    :class: woke-ignore
.. role:: vale-ignore
    :class: vale-ignore
"""

Then apply these roles to specific terms within your documentation:

This is an ignored word: :vale-ignore:`foo`.

This is configured by default in Vale's configuration file so it is available for all users. There is also a specific 'woke-ignore' class that will... do the exact same thing. I need to rethink that implementation.