Add spec to verify that the connection expires

[winebarrel]

I added a test to verify that the connection expires in Rails. (Travis CI has passed)

Would you merge it if there is no problem?

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The procedure of a test is as follows:

1. start mysql server
2. bundle install
3. bundle exec rake

[sonots]

Thanks, but I do not want to push rails codes.
Is it possible to write tests depending with only rack and AR?

[winebarrel]

Thank you for reply :-)
I can not fix it soon, but I'll try.

[sonots]

: )