Preserve paragraph breaks in summary

Converted each closing p-tag and its surrounding whitespace into two newlines.

Because some newlines are being preserved I changed the later \s character class into [ \t\r\f\v].

Included a test. The expected summary is a bit long for my taste but because of whitespace between tags I thought it was best to use real data instead of simpler conjured data.

Let me know if any of my changes don't adhere to your style and I'll make the appropriate changes.