[i18n-activity] Complex ruby is usually both mono and group ruby

r12a has just created a new issue for 
https://github.com/w3c/i18n-activity:

== Complex ruby is usually both mono and group ruby ==
10.2.33 tts:ruby
Example Fragment – Complex Ruby
https://www.w3.org/TR/2016/WD-ttml2-20161117/#style-attribute-ruby-example-2-images

A much more representative example of complex ruby would show 
mono-ruby before and group ruby after.

`<span tts:ruby="text">とうなん</span>` should be changed to 

`<span tts:ruby="text">とう</span><span tts:ruby="text">なん</span>`


Please view or discuss this issue at 
https://github.com/w3c/i18n-activity/issues/315 using your GitHub 
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