[css-writing-mode] change a structure of text-baseline test cases.

Hi Gérard,

I change a structure of text-baseline-***.html.

Points are following.
1. Test files are divided into more fine test case.
2. Each test case contains a one test case and is named a combination of
writing-mode property and text-orientation property. (e.g.
tb-sideways-left).
3. Files which have same number may have a same reference file.
   For example, the following files will have same reference file.
   + text-baseline-002-lr-sideways.xht
   + text-baseline-002-lr-sideways-left.xht
   + text-baseline-002-rl-sideways-left.xht
4. I will apply the change to the others if this time change is no problem.

I consider about creating a reference file using a new font you discuss
about now.

New test files are following.

https://github.com/hshiozawa/csswg-test/blob/master/css-writing-modes-3/text-baseline-001-tb-mixed.xht
https://github.com/hshiozawa/csswg-test/blob/master/css-writing-modes-3/text-baseline-001-tb-sideways-left.xht
https://github.com/hshiozawa/csswg-test/blob/master/css-writing-modes-3/text-baseline-001-tb-sideways-right.xht
https://github.com/hshiozawa/csswg-test/blob/master/css-writing-modes-3/text-baseline-001-tb-sideways.xht
https://github.com/hshiozawa/csswg-test/blob/master/css-writing-modes-3/text-baseline-001-tb-upright.xht
https://github.com/hshiozawa/csswg-test/blob/master/css-writing-modes-3/text-baseline-001-tb-use-glyph-orientation.xht
https://github.com/hshiozawa/csswg-test/blob/master/css-writing-modes-3/text-baseline-002-lr-sideways-left.xht
https://github.com/hshiozawa/csswg-test/blob/master/css-writing-modes-3/text-baseline-002-lr-sideways.xht
https://github.com/hshiozawa/csswg-test/blob/master/css-writing-modes-3/text-baseline-002-rl-sideways-left.xht
https://github.com/hshiozawa/csswg-test/blob/master/css-writing-modes-3/text-baseline-003-lr-sideways-right.xht
https://github.com/hshiozawa/csswg-test/blob/master/css-writing-modes-3/text-baseline-003-rl-sideways-right.xht
https://github.com/hshiozawa/csswg-test/blob/master/css-writing-modes-3/text-baseline-003-rl-sideways.xht
https://github.com/hshiozawa/csswg-test/blob/master/css-writing-modes-3/text-baseline-004-lr-mixed.xht
https://github.com/hshiozawa/csswg-test/blob/master/css-writing-modes-3/text-baseline-004-lr-upright.xht
https://github.com/hshiozawa/csswg-test/blob/master/css-writing-modes-3/text-baseline-004-lr-use-glyph-orientation.xht
https://github.com/hshiozawa/csswg-test/blob/master/css-writing-modes-3/text-baseline-004-rl-mixed.xht
https://github.com/hshiozawa/csswg-test/blob/master/css-writing-modes-3/text-baseline-004-rl-upright.xht
https://github.com/hshiozawa/csswg-test/blob/master/css-writing-modes-3/text-baseline-004-rl-use-glyph-orientation.xht

Now I am working on my github repository.
If you prefer hg.csswg.org to github (or hg repository is easy to review
for you), I will work on hg.csswg.org.
-- 
# 塩澤 元 (Shiozawa, Hajime)
# mail: hajime.shiozawa@gmail.com