Change SugarTest output

Now gives some result summary and shows the last test added. Showing the
last takes makes it easier to comprehend if the desugaring failed for a
new test and the tests are just executed from cache.
Add test for multiple args on elem without content
Add desugaring for one nested element (no text)
Add desugaring for one nested text element
Add desugaring for many children in one element
Add desugaring for elem with children and attributes
Add support for multi-line text elements