nl_tokens: returns rel path of src from root
pl_tokens: function rel ( <mask> , src , sep ) { if ( ! root || ! _ . isString ( root ) || ! src || ! _ . isString ( src ) ) return let root_split = root . split ( path . sep ) , src_split = src . split ( path . sep ) return _ . join ( _ . difference ( src_split , root_split ) , sep || '/' ) }