v1.3

• device_c:
  • use read_words library for use_dev command (allow multi-line and quoted strings)
  • allow multiple argments in ask command
  • options can appear only before a non-option argument
• drivers:
  • add serial_et driver for EastTester devices
  • drv_serial: fix reading in non-blocking mode
  • drv_gpib: -delay parameter
  • drv_gpib: argument of -eos_mode option is any combination of X R B flags
• unlock action: do not return error if device is not locked
• update Readme.md