Tweak some defaults: `macro_names`, `operator_spaces`, `no_space`, `function_naming_convention`, `module_naming_convention`, `no_debug_call`

[paulo-ferraz-oliveira]

As per discussion under the issue this closes. Closes #234.

Documentation and migration guide are updated.

Further considerations

Potentially best reviewed on a commit-by-commit basis: everything except the documentation updates is pretty isolated.

[paulo-ferraz-oliveira]

Strange that this is flagged as merged and closed 😄