Case sensitive generate model yaml

[Thrasi]

resolves #188

This is a:

• documentation update
• bug fix with no breaking changes
• new functionality
• a breaking change

All pull requests from community contributors should target the main branch (default).

Description & motivation

Working with a database that has capitalised model and column names, the result of generate_model_yaml.sql doesn't match the database because generate_model_yaml lowers all names.
I added optional parameters to the macro to toggle this behaviour. Similar functionality has already been added to generate_source.sql. I see no reason why this shouldn't be supported for models.

Checklist

• This code is associated with an issue which has been triaged and accepted for development.
• I have verified that these changes work locally
• I have updated the README.md (if applicable)
• I have added tests & descriptions to my models (and macros if applicable)
• I have added an entry to CHANGELOG.md

[henry-yu-gce]

I also had this issue with generate_model_yaml. Did this end up being resolved some other way since I see that this PR is not merged.

[Thrasi]

@henry-yu-gce I didn't have time to follow up on it but the issue #188 was closed since there was a similar one open #175
Which hasn't been resolved.
The changes worked as I expected, but the test I introduced didn't work with postgres all tables are lower cased.

But I haven't studied this with the added context of #188