fixed prettify google if you have put the language in code block markdown
Merge pull request #314 from simonini/master

fixed prettify google if you have put the language in code block markdow...
Add a changelog entry for #314
Move the prettify test to the HTML render tests

Test introduced by #192 wasn't located in the good file.
Improve prettify feature testing

Actually, the test introduced by #192 for this ferature wasn't
covering anything since the backticks were escaped so the output
was generate by the codespan callback.

This commit should test this feature almost correctly and reflect
changes done in #314.
Merge branch 'master' into copy-block-for-converter
Add test