- Replace TableExt with a Config trait that extends toml::value::Table
Add configuration for add_newline
- add_newline is a root-level configuration value. When set to false, the initial newline before the prompt is removed.
- Create `Config` struct that is added to `Context` when initialized
- Read `~/.confg/starship.toml` during initialization (can be updated later to also look at `$XDG_CONFIG_HOME`)
- `Context` now has a method for creating modules. This allows us to provide modules with a reference to the configuration specific to that module
