Avoid interpreting a cell-closing "|" as a new table

[melloc]

I noticed that the bugview server got stuck parsing OS-7093. Upon closer inspection realized it was because it had markup like this:

| A | - | - |
| B | - | - |

When the parser first encounts the -, it thinks that it needs to parse a list. When it then encounters the |, it thinks that it's parsing a table inside a list element, rather than closing the table.