crit/decode: set default opts['nopl'] to False

to fix error:

./crit/crit decode -i test/dump/zdtm/static/maps04/118/1/stats-dump
Traceback (most recent call last):
  File "./crit/crit", line 276, in <module>
    main()
  File "./crit/crit", line 273, in main
    opts["func"](opts)
  File "./crit/crit", line 28, in decode
    img = pycriu.images.load(inf(opts), opts['pretty'], opts['nopl'])
KeyError: 'nopl'
Signed-off-by: Pavel Tikhomirov <ptikhomirov@virtuozzo.com>
Signed-off-by: Pavel Emelyanov <xemul@virtuozzo.com>

crit/crit

@@ -236,7 +236,7 @@ def main():
 	decode_parser.add_argument('-o',
 			    '--out',
 			help = 'where to put criu image in json format (stdout by default)')
-	decode_parser.set_defaults(func=decode)
+	decode_parser.set_defaults(func=decode, nopl=False)
 
 	# Encode
 	encode_parser = subparsers.add_parser('encode',