Fix inconsistencies with serde and add SCREAMING-KEBAB-CASE

[escritorio-gustavo]

Goal

This PR aims to fix a few inconsistencies with serde caused by our use of inflector:

• Fix snake_case inconsistency
• Fix SCREAMING_SNAKE_CASE inconsistency
• Fix kebab-case inconsistency
• Add SCREMING-KEBAB-CASE
• Remove dependency on inflector
• serde only accepts the rename_all rule if the case is written exactly as described (i.e. CAMELCASE, Kebab-case, etc. are not allowed), where as ts accepts any changes in case, dashes and underscores. This was changed for consistency with serde

Closes #297

Changes

• Manually implement snake_case like in serde
• Change parse_assign_inflection to only accept cases written strictly like in the docs
• Add Inflection::ScreamingKebab
• Remove dependency on inflector

Checklist

• I have followed the steps listed in the Contributing guide.
• If necessary, I have added documentation related to the changes made.
• I have added or updated the tests related to the changes made.

[escritorio-gustavo]

serde only accepts the rename_all rule if the case is written exactly as described (i.e. CAMELCASE, Kebab-case, etc. are not allowed), where as ts accepts any changes in case, dashes and underscores. This was changed for consistency with serde

@NyxCode this is the only "unnecessary" change here, though I think it's beneficial, as it forces the user to use the case they are setting rename_all to, which helps make sure they are using the correct one (e.g.: a common mistake is using CamelCase instead of PascalCase). Since the changes to snake_case, kebab-case and SCREAMING_SNAKE_CASE make this whole PR a breaking change, I thought it'd be a good time to change this.

Still, this is an extra breaking change, let me know if you want me to revert it

[NyxCode]

Nice change, thanks!
I'm not sure regarding the breaking change, but I think it's alright, since we publish major versions relatively often anyway.

[NyxCode]

great stuff!