Re-write AES-CTR implementation to simplify. Plain/ciphertext lengths may be arbitrary, key schedule is only invoked once
Use the new aes256CtrSetIv() in the AES-CTR tests
Shuffle the call to incrementCtr() to match the expectation of the test code
Remove unused variable
Apply jim17's suggestions
Fix overflow (per jim17)
Merge pull request #26 from henryk/aes-ctr

Simplify and generalize AES256-CTR code