[iip] Upright text in vertical lines doesn't segment correctly (#85)

r12a has just created a new issue for https://github.com/w3c/iip:

== Upright text in vertical lines doesn't segment correctly ==
Upright characters in vertical lines of text don't break correctly, due to the problem of detecting syllable boundaries correctly mentioned above. Marking this as advanced, since syllable boundary identification and appropriate breaking is not happening in any of the browsers. 

See requirements at: <a href="https://w3c.github.io/ilreq/#h_vertical_arrangements_of_characters">Indic Layout Requirements</a>

Please view or discuss this issue at https://github.com/w3c/iip/issues/85 using your GitHub account