easily removable error warning when saving to new json file

[doutriaux1]

In [1]: b=x.createboxfill()

In [2]: b.script("dsdfsfd")
Error reading json: dsdfsfd.json No JSON object could be decoded

In [3]:

[doutriaux1]

@aashish24 ready for review

[aashish24]

@doutriaux1 code looks good. One minor suggestion though if you may: Please use the variable with more than one letter to explain what it is:

D = json.load(f)

•    except Exception,err:
  

•      print "Error reading json file, will be overwritten",fileout
  

•      D = {}