Removing timezone to enable escaping

Hi All-
There is an issue here related to #219 where PyMySQL should strip the timezone from the datetime before inserting. Right now it is failing on the insert, since mysql doesn't take timezone info.

Thanks!
Ahh correct, perhaps this was a mistake on my part. I can't really remember the exact use-case for why this was specifically changed. I did notice it failed integration tests, so most likely this is an error.