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Thanks to @chesleybrown for adding support for a generic tcp/udp checker in #47!

Fixed state read race reported in #45; fixed an incorrectly placed defer resp.Body.Close().

Thanks to @schigh for contributing failure/recovery callback functionality!

Another minor release that allows the global failed state to recover after a previously failed (and fatal) check recovers.

@schigh contributed an awesome, extensible SQL checker - nicely done!

• Fixed a goroutine leak after .Stop() is called
• States now actually get reset after .Stop() is called
• Minor test cov increase

This is the initial release!