increase attempts and timeouts for http push

With this change we try to http-PUT the file up to 10 times with increasing delays between the attempts up to 256s.

Note that I moved the sleep call at the beginning and I added a first fake sleep of 0s. The way the code was written before, in case of problems we had one attempt immediately, a sleep of one second, another attempt, a sleep of 2s, a last attempt and a sleep of 4s before printing the failure message.