Added stepper class to interpreter so now an intrinsic call like moveAbsolute() can be made directly to the motor. As a result, the log file now includes all the stepper acceleration curve information, but you'll also see 3 calls to moveAbsolute(7), moveAbsolute(9) and moveAbsolute(11), from valve4.def.
The Makefile has been updated to build the stepper files from the motor project. That is located in the motor git repository which is at the some level as the parser.
Removed old stepper test code that was #if'd out in the interpreter. The same code was moved over to the stepper long ago and is no longer needed in the interpreter.

One task that still needs to be addressed in the interpreter is to consolidate nodeTemporary variables and sweep them back into nodeAvailable after their use. Just a note to not forget this otherwise the symbol table will quickly be exhausted.