(Bug 70894) Fix bugs serializing modified wikilinks

* Fixed serialization of simple category links (strip leading "./" and
  normalize '_' to ' ').

* Fixed detection of isSimpleWikiLink case by normalizing hrefs
  (by replacing '_' to ' ' first).

* Found a missing /g/ flag on a regexp replace. A number
  of previously blacklisted tests change their output because
  of this. The new output is correct.

* Added a new parser test.

Change-Id: I61cf366c481591f21d92983b941bc87e4923cd15
Merge "(Bug 70894) Fix bugs serializing modified wikilinks"