Colored diff

[ksss]

I added color by default to the diff format of the rbs diff command.

# t.rbs
class Foo
  def a: () -> void
  def c: () -> void
end

# tt.rbs
class Foo
  def a: () -> void
  def b: () -> void
  def c: () -> void
end

Refactoring

Rename from RBS::Diff::CLI to RBS::CLI::Diff

Previously, we had a namespace for the Diff feature, but there were two more general CLI classes, making it confusing.
We've changed the name and placed the class for the Diff feature under the CLI class, renaming it to CLI::Diff.

Rename from RBS::Collection::ColoredIO to RBS::CLI::ColoredIO

We wanted to use ColoredIO within the CLI layer, but using Collection::ColoredIO at the CLI layer felt odd.
Moving ColoredIO to the CLI layer still felt natural within the Collection layer, so we made the shift.

[soutaro]

👍