Add category label

[pierrick-pluchon]

Hi @cw-sakamoto !

First of all, thanks for your hard work on this repo.
It helps us tremendously!

Quick question, any reason to have removed the category 2 years ago with this commit 38788ef ?
I do not see any documentation about it(not even in the commit body).

Could you consider adding it again?

Thanks for your help.

[pierrick-pluchon]

Hi @cw-sakamoto !

Any news about this ? :)
Thanks a lot