Add functionality for atomic file creation via unix rename

[oschulz]

No description provided.

[theHenks]

I think this is good to have to replace this functionality which is currently done manually in the julia-data-flow. Here, I usually do the following:

@debug "Create DSP folder"
  dsp_folder = l200.tier[:dsp, :cal, period, run]
  if isdir(dsp_folder)
      @debug("DSP folder $dsp_folder already exists")
  else
      mkpath(dsp_folder)
  end

  @debug "Create logs folder"
  log_folder = joinpath(l200.tier[:log, :cal, period, run])
  if isdir(log_folder)
      @debug("Log folder $log_folder already exists")
  else
      mkpath(log_folder)
  end

[theHenks]

Done with latest PR