Replace all uses of echo with printf:
- It is not possible to terminate the argument list of echo so if we run into a string which starts with "-" and an echo parameter it would use it as parameter. See http://mywiki.wooledge.org/BashPitfalls#echo_.24foo
- I've also reviewed all uses of the function which use echo indirectly by searching for the regexp (echo|log|stdout|stderr|log_and_stdout|log_and_stderr|die) in the script. When reviewing them, I made sure that they do not need echo parameters and that their use of multiple parameters works with the new printf code. The latter especially applies to the removed space in the "ERROR:" string at log_and_stderr, it was duplicate.