Minor Breaking Change - Move Some BaseWriter Properties

[oleibman]

When Conditional and Table Formatting were added to Html Writer, properties, getters, and setters were added to Base Writer. They should have been added to Html Writer instead, and this PR moves them from one to the other. It is technically a breaking change, but, since there is no reason to use them with any writer other than Html, I don't anticipate anyone seeing any adverse effects.

This is:

• a bugfix
• a new feature
• refactoring
• additional unit tests

Checklist:

• Changes are covered by unit tests
  • Changes are covered by existing unit tests
  • New unit tests have been added
• Code style is respected
• Commit message explains why the change is made (see https://github.com/erlang/otp/wiki/Writing-good-commit-messages)
• CHANGELOG.md contains a short summary of the change and a link to the pull request if applicable
• Documentation is updated as necessary