retry 3 times on network issues

[shoeper]

I had issues with ('Connection aborted.', ConnectionResetError(104, 'Connection reset by peer')) and ('Connection aborted.', RemoteDisconnected('Remote end closed connection without response')) which could be solved by retrying up to three times.

[whoot]

Hi, this seems to be a network issue and not something tool related.
Also instead of printing the error message on every failed connection, it would be better to do the retries first and if it fails on the last retry print the error message.

[shoeper]

Hi, I agree it is no problem of the tool, but the webserver had issues. So I couldn't test it with typo3scan until hacking this fix. Submitted it in case somebody runs into a similar issue. Actually, I'm not sure on the error message, because it may still be something one wants to be aware of.