This exercise tests your understanding of nondeterminism in language
definitions and how you can make use of K's features to explore it.

Most of the programs in the tests directory exhibit nondeterministic
behavior.  Your main task is to make that behavior manifest, such that
it matches the provided output files (if executed with the contents of
the provided input files as input).

There is also a nondet-my.imp.out file with no corresponding program.  
To make this test pass you will need to provide a nondet-my.imp file 
containing a program which could produce any of the solutions in 
nondet-my.imp.out as a possible result of the execution.

Hint:  Check lesson_3 and lesson_7 of the IMP++ tutorial.
