Updated to Python 3

[MatthewBoeding]

Tested using python 3.10.12

Changes:

• Path resolution for single directory library
• Removal of Python 2 syntax
  • long() function no longer needs called
  • Removed "L" suffix as all integers are long in Python 3
  • ord() function not required for byte to integer conversion
  • xrange() transitioned to range()
  • sys.maxint no longer required for long to int concatenations
• Bit fields updated for DNP3RequestDataObjects()
  • BitFields "Obj" and "Var" updated to 8 bits from 4
• Created Example script of packet generation

To Do:

• Data chunk decoding
  • Number of items, Point number, control code, count on/off time and control status should be implemented