Document what TableComponent each char in a preset is mapped to

[tisonkun]

I made a style:

const TABLE_STYLE_PRESET: &str = "||--+-++|    -+++++";

With several times attempt for understand what each char means.

Although we have current_style_as_preset as a helper, document what TableComponent each char in a preset is mapped to would make this magic string more understandable.

[Nukesor]

Does the documentaton on load_preset help you?
https://docs.rs/comfy-table/latest/comfy_table/struct.Table.html#method.load_preset

Feel free to create an MR to link to those docs at the places you feel they should be linked from :)

[Nukesor]

#168 and #167

Those need a few regression tests that fail on main first, before fixing them for good.
I would also like to get a proper understanding on how to fix them and whether other pieces might be affected as well :D
Correct UTF-8 handling really is tricky.