Add MySQL language support (again)

Hi again.
I redo my pull request on the good branch "2.5" instead of branch "master".
I fixed the bug with the MySQL's URL and spaces.

>Hi, it probably already exists, but I added a MySQL language support.
This is useful when you want the day name or the month name (for exemple) in a date if you have a blog.

Thank you for your reading.

(Sorry, bad english)