Split PlRubyTag.NoRubyText into two tests.

I've split PayloadRubyTag's unit test NoRubyText into two tests because they were testing
two different cues at once that were slightly difference. We want to keep these tests as
atomic as possible so it makes sense to split them up.
Merge pull request #215 from RickEyre/no-ruby-text-fix

Split PlRubyTag.NoRubyText into two tests.