Replace md5 module with hashlib

fix following pylint error:

************* Module connectors.ConnectorBase
connectors/ConnectorBase.py:7: [W1648(bad-python3-import), ] Module moved in Python 3
************* Module runtime.PLCObject
runtime/PLCObject.py:33: [W1648(bad-python3-import), ] Module moved in Python 3

#!/bin/bash

INKSCAPE=inkscape

for i in `cat icons.svg |grep -o -e '%%[^%]*%%'|sed 's/%//g'` 
do
 if [ $i.png -nt icons.svg ]; then
 	echo "Skip $i"
 else
	rm  -f $i.png
	echo "$INKSCAPE" icons.svg -z -e $i.png -i $i
	"$INKSCAPE" icons.svg -z -e $i.png -i $i
 fi
done