NewPortXYZ stepper working (use rs323 v0.3.5 with CR+LF appenning).
modified:   Makefile: upgrade to version v0.2.3 .
modified:   VERSION: version v0.2.3 .
modified:   _info.txt: add NewPortXYZ stepper (ESP300) examples.
modified:   stepper.cpp: add NewPortXYZ stepper (ESP300) example in usage.
modified:   stepper.help.output: auto updated.