Rewrite "Italics and bold" test cases so that they should work on Parsoid.

There is still a bug in Parsoid's WTS which causes some of these tests
to fail, documented in bug 63119.  The next patch will fix these
failing tests.  But all the failures in the test cases are now *real
bugs*, not artifacts of our normalization or <nowiki> insertion.

Change-Id: Ic846e360c2882fe99c119dc0978f08bbbc73cc78
Merge "Rewrite "Italics and bold" test cases so that they should work on Parsoid."