Add method to check that file with these extension is supported by this package

[sumitsharansatsangi]

Add method to check that file with these extension is supported by this package

Although , in the ReadMe.md file , there is a link of rehighlight package to guide which language but there is no method to check.

[heckmon]

Do you mean this link?

Also, if a language isn't supported, you can either use the Mode() class like this for rendering the plain text:

CodeForge(
     language: Mode()
)

or load/create a TextMate grammar:

CodeForge(
     language: CustomLanguageGrammar.fromJson(your TextMate grammar)
)