Import libxo-0.8.0:

• addition of --libxo colors=xxxxx color map (so I never see "blue")
• fix bugs from -fsanitize=address and =undefined
• utf-8 changes (remove support fore 6 byte utf-8 values, which are "historical")
• add comments
• fix man pages
• update test cases

Submitted by: phil
Reviewed by: sjg
Approved by: sjg (mentor)