Cover basic and colored output regressions with unit tests

[50U10FCA7]

Resolves #299

writer::Basic seems to be broken when outputting in color mode.

writer::Basic::lines_to_clear counts more lines than need be cleared. Duplication of #300

Cover basic and colored output with unit tests.

Additionally:

• Use deterministic order of possible matches in AmbiguousMatchError;
• Reduce count of cursor moves in writer::out::WriteStrExt::clear_last_lines;
• Unify code style of lines accessing writer::Basic.