Retry logic and more error reporting

Having real struggles with the addon at the moment... deploy job keeps stuttering to a halt, but wp2static shows it as processing forever. Nothing in wp2s logs or php logs, but deleting and re-adding the deploy job will eventually process everything - so it can't be a fatal block - but I think some retry logic or more verbose error logging would really help pin this down - currently I'm at a loss at to the ultimate cause.