Allow configuration of filetypes

[William Heinbockel]

Currently, coc-markdownlint is hard coded to only load for markdown filetypes.

This is problematic if you try to load coc-markdownlint in combination with alternate markdown syntax such as vim-pandoc. I usually have my markdown files set to pandoc or markdown.pandoc -- either of which cause this extension to not load.

I would suggest either allowing a wildcard filetypes that include markdown or allowing the user to configure this via a markdownlint.filetypes array configuration option in coc-settings.json.

[Heyward Fann]

Add this to your vimrc:

let g:coc_filetype_map = { 'pandoc': 'markdown' }

This will not change your filetype, and coc will treat it as markdown.

[Matthew Toohey]

Hello! The fix posted above worked well for me initially, but I now have a use-case that I don't think this solves: I'd like to use coc-r-lsp and coc-markdownlint at the same time on an R markdown document, but if I set the filetype map from rmd to markdown, then coc-r-lsp stops working. Is there another work-around for this use case, or a way to use the filetype map to map to more than one filetype at once?