Set sensible defaults for timeout and connection timeout

[Spriz]

I wasn't sure if it should be added to the https://github.com/lorenzo/cakephp-sqs/blob/master/README.md - but at least this will ensure nobody is caught by this gotcha - we've had sporadic issues for almost 3 years because of this before we sat down with strace and figured out why the processes was hanging

[Spriz]

I'm aware the change will cause crashes for somebody, but on the other hand having a process hanging and never doing anything is probably never really the wanted case IMO