(Bug 52762) Lines with 1+ comments and WS are transparent to handlers

* This was being handled exlicitly in pre- and paragraph- handlers
  and the list handler wasn't yet handling this special case.

  The PHP preprocessor strips out such lines from wikitext which
  effectively means that Parsoid needs to pass through those lines
  without changing state of any handler in the pipeline.

* This commit updates the "sol" production to collect these empty
  lines and wrap them in a meta-token which all handlers ignore
  which are re-expanded in the HTML tree builder.

* Removed custom code from the paragraph handler.

* Tweaked the list-handler to close list elements at end of line.

* Added an additional rule to the output normalization code to
  strip such lnes from output.

* 5 wt2html tests (and some associated selser tests) are now green.
  Selser tests got changed around because of tweaks to some
  parser tests and because of minor changes in HTML output.

* Minor unrelated cleanup to TSP left behind from an earlier gerrit
  patchset for this commit.

Change-Id: I6aada39ff966c328688b085c4b1ba4c46faf713c
(Bug 53135) Step 1: Always use parts array for transclusion data-mw

* Got rid of the special case for the case of template content
  producing a well-formed DOM subtree. This also eliminated
  code in table-fixup passes that dealt with the special case.

* Both serializer and VE can handle the general case properly so
  this should be safe for production deploy.

Change-Id: Id29213a52597dda93063ad93938201b77cacd658
Merge changes Id29213a5,I6aada39f

* changes:
  (Bug 53135) Step 1: Always use parts array for transclusion data-mw
  (Bug 52762) Lines with 1+ comments and WS are transparent to handlers