Add an option to enable it in any language, instead of using enabledLanguageIds

[lucasdf]

Hi there!

How would you feel about having an option to run coc-spell-checker in any language? I think this would be a good complement for the current configuration, which only runs it on the files specified in enabledLanguageIds.

Do you think a new configuration like cSpell.enabledForAllLanguages could be added?

[alexesba]

Probably adding a new property customLanguageIds = ["conf", "text", "otherfiletype", "etc.."] would be a better option.
and then internally extend the enabledLanguageIds with the customLanguageIds in that way the users will be able
to keep the current configuration and be able to add custom languages if needed.