Use tab-line for Emacs 27

[AmaiKinono]

Emacs 27 has tab-line for displaying tabs. A benefit of using it is we can have both header-line and tab-line displayed. See this:

This is M-x list-packages. tab-line is used to display tabs, and header-line is used to display the header of the table. An obvious benefit is we no more need to hide tabs for such buffers, like *Flycheck Errors*.

You may want to:

• Test this patch. I didn't test it thoroughly so there may be problems.
• Edit the hide rules. I choose to show tabs in *Compile-Log* and *Flycheck Errors* buffers. I don't know *lsp and *epc in your code, maybe they can benefit from this too.

[manateelazycat]

Thanks man