Add support for Unicode character border

[silkfire]

Would it be hard to add an option to use a Unicode border instead?

Similar to what this tool has as an option: https://www.tablesgenerator.com/text_tables#

[mookid8000]

Yeah well, if I remember correctly the code is a little bit convoluted and not really prepared to be extended.

Would be a fun refactoring though, to make it extendable like that.

There's plenty of tests to verify that the current behavior is not broken.

[silkfire]

See it as a challenge!