Add forward_missing_to @object to Colorize

[wyhaines]

While working with code in a few other areas, including Benchmark::IPS, I tripped a little over the fact that a colorized String (or any other object) becomes an instance of Colorize::Object(T), and can no longer be used as it's original object type.

There are many times where one may want to inject some color or mode changes into a String and still transparently use the resulting object as if it were a String.

This patch adds a forward_missing_to @object, which in most cases where the type signature allows it, lets a colorized object like a colorized String duck type its way through life as if it were still a String, which simplifies many things.

The patch also adds a mode method like the fore and back methods, because without it, forward_missing_to caused spec failures. I also added a basic spec to exercise the method forwarding as part of this change.

[straight-shoota]

This doesn't click with me right away. Could you detail a bit about your use cases? Ideally, please create an issue for this so we can separate general discussion about this feature from the concrete implementation in this PR.

[asterite]

and still transparently use the resulting object as if it were a String

In my mind colorize is the last thing you call before moving that object into the output. If you need to do some things with the original string, I would preserve that as a separate variable.

I think adding forward_missing_to would make things a bit harder to understand.

[wyhaines]

As requested, to short circuit a lot of discussion on the PR, I have created an issue:

#13007

[wyhaines]

I am closing this PR, having been convinced that the use case isn't generally worth the potential downsides.