Remove deprecated methods from Options and Attributes

[abelsromero]

New Builder methods have been available for several versions and I think it's time to remove them to simplify code. The goals are:

• Reduce code
• Stream line the API: no more having multiple ways to create Options or Attributes. The only exception are the get() Map methods maintained for convinience.

This does not suppress https://github.com/asciidoctor/asciidoctorj/issues/977, that was a good conversation and there's room to improve, this is just to remove what we already agree to clean code.

[abelsromero]

I think this could be the last milestone for v3.0.0? Or is there anything else that we should add?

[abelsromero]

Working on it I see there are also the deprecated methods in the Asciidoctor interface, I'd rather deal with that in another PR. I'll create another issue to track tath.

[abelsromero]

Found also methods in Document to remove.