Add a runner script for cryptotest.

Add a runner script for cryptotest.

Althought cryptotest itself has a -z mode to test all algorithms at a variety
of sizes, this script allows us to be more selective.  Threads and buffer sizes
move in powers of two from 1, for threads, and 256 for buffer sizes.

e.g.  cryptorun.sh aes 4 512

Test aes with 1, 2 and 4 processes, and at sizes of 256 and 512 bytes.

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