(PDOC-17) Fix up parameter documentation

Prior to this commit there were a few issues in the way information
about parameters was collected. The previous implementation relied
on parameters and their corresponding comments to be listed in the
same order. Now the parameter is matched to the corresponding comment
using the parameter name in the comment.

Additionally, if a comment is present for a parameter that does
not actually exist in the method it will appear as strike through
in the HTML.