Suggestion: Provide a delimiter for comments

I often have trouble using regular expressions with easy-align and I think I've tracked it down to #53: it's probably always with aligning comments.

Could easy-align provide a comment delimiter that uses `commentstring` to determine the pattern?

Something like this:

" Provide a / delimiter for the current filetype's comment marker.
augroup easyalign_comment
au!
au BufEnter * let g:easy_align_delimiters['/'] = { 'pattern': substitute(&commentstring, '%s.*', '', ''), 'ignore_groups': ['!Comment'] }
augroup END