Added support for {{echo|style='color:red'}} style attr. templating

* Real use case on French wikipedia {{ligne grise}} found on this
  page fr:Coupe_UEFA_1972-1973. I wouldn't be surprised if equivalent
  templates exist on enwp and are used elsewhere. Since we had supported
  this use case till now, we may not have run into production errors on
  those. So, adding back the support that was dropped in 283bfd55.

* Fixes the parser tests that failed and were blacklisted in 283bfd55.

* Fixes RT errors on fr:Coupe_UEFA_1972-1973

Change-Id: I8119d753a02d10c8db48db8dfaac8c46dba981df