User IO overhaul

What's Changed

• Overhauled user IO by @asciifaceman in #2

Full Changelog: v0.1.0...v0.2.0

First Release: Underlying color API

• Icolor and Icolorf provide wrappers for colorable text that checks the FD first and provides indents
• Opinionated wrappers such as Success, Error, Warn, etc
• Some early work on structural elements like Headers
• Very early work on userio that isn't using the underlying API yet but will in the next release