(Bug 52618) Suppress <nowiki>s for table WT strings outside tables

* This patch follows up on c912f73b.
* Eliminates html2wt failure of one test but introduces a html2html
  failure because wt2html doesn't handle that wikitext correctly.
* The following pages no longer get nowikis added around "|" anymore:
  http://localhost:8000/_rt/eswiki/Luis_Velasco_%28futbolista%29
  http://localhost:8000/_rt/arwiki/%D9%83%D8%A3%D8%B3_%D8%A7%D9%84%D8%A3%D9%85%D9%85_%D8%A7%D9%84%D8%A3%D9%81%D8%B1%D9%8A%D9%82%D9%8A%D8%A9_%D9%84%D9%83%D8%B1%D8%A9_%D8%A7%D9%84%D9%82%D8%AF%D9%85_2015

Change-Id: I784bd4b6867f8ca3e4b2c920ee3cad6c827db40b