doc: leave out too large samples

To let compilation of the document succeed, this patch leave out
large samples.

Signed-off-by: Yoshihiro Kaneko <ykaneko0929@gmail.com>
Signed-off-by: FUJITA Tomonori <fujita.tomonori@lab.ntt.co.jp>
doc: improve the appearance of the table

I don't want to write a directive of sphinx in scripts, but
I was not able to find other methods.

Signed-off-by: Yoshihiro Kaneko <ykaneko0929@gmail.com>
Signed-off-by: FUJITA Tomonori <fujita.tomonori@lab.ntt.co.jp>