Alacritty toml files

[kstevens715]

Alacritty now uses yml configuration files instead of yml.

For example, using the existing yml files I now get this warning:

I could attempt to make a PR that adds a new shipwright runner if you're interested in supporting this. If so, would you rather the new toml runner replace the existing yml runner or continue generating both yml and toml files?

[kstevens715]

I ended up creating an initial PR: #158.

[mcchrish]

Let's generate toml only moving forward. The yaml ones can still be accessed from previous versions if needed.

[kstevens715]

Let's generate toml only moving forward.

I've updated the PR to only generate toml.