Append e to current buffer.

Property definitions

markdown $ MarkdownProcessor :: add
	# Append `e` to current buffer.
	fun add(e: Writable) do
		if e isa Text then
			current_buffer.append e
		else
			current_buffer.append e.write_to_string
		end
	end
lib/markdown/markdown.nit:595,2--602,4