Previously some of the writers added spurious whitespace.
This has been removed, resolving Issue #232.
NOTE: If your application combines pandoc's output with other
text, for example in a template, you may need to add spacing.
For example, a pandoc-generated markdown file will not have
a blank line after the final block element. If you are inserting
it into another markdown file, you will need to make sure there
is a blank line between it and the next block element.