Format of extern cpu select module (shuffle):

Any program, which gets on stdin this line:

N cpu1 cpu2 ... cpuK

where
       N - number of processors
       cpu1..N - available processors names
       all elements are separated by space.

Program must return to stdout line:
cpuX1 cpuX2 ... cpuXN

cpuX1...cpuXN must be taken fron given list. All elements are
separated by spaces. Number of elements must be N.
