css-writing-modes-3: test for text-combine-upright on full-width characters

http://www.w3.org/TR/2014/CR-css-writing-modes-3-20140320/#text-combine-fullwidth says:

> when the combined text consists of more than one character, then any full-width
> characters must first be converted to their non-full-width equivalents

add two test cases and a reference to check that.

* full-width-001.html -- it has full-width characters directly input in the doucment.
* full-width-002.html -- it uses `text-transform: full-width` to achieve the effect.
Merge pull request #558 from myakura/myakura/text-combine-upright-9_1_3_1

LGTM: css-writing-modes-3: test for text-combine-upright on full-width characters