Replace cyrillic 'и' by 'and' to avoid LaTeX error

Hi,

Currently there is a LaTeX error caused by a cyrillic letter in spec/text_spec.rb. I am proposing to replace it by its English translation 'and'.

Thanks.

Cédric
Merge pull request #422 from boutil/patch-1

Replace cyrillic 'и' by 'and' to avoid LaTeX error