Make long item labels on enumerated lists work.

There were two failures with long numerical item identifiers.

A single item with a long identifier would turn into two nested lists, one that trimmed off the e.g. 1000 and another that used the remaining 00. as it's identifier.

    100000. An item

Once that was fixed I noticed that there was a problem pulling additional paragraphs into the list item.

These changes fix both issues.

This change also removed some insignificant whitespace from the html output which required fixing an existing test.