Bug 1022343 - Use the hash function's block size as the default length when generating keys
Bug 1021607 - Introduce BasicSymmetricKeyAlgorithm
Bug 1021607 - Implement import key operation for PBKDF2 r=bz,rbarnes
Bug 1021607 - Introduce MapAlgorithmNameToMechanism()
Bug 1021607 - Implement derive bits operation for PBKDF2
work on deriveKey()
Revert "work on deriveKey()"

This reverts commit 25f560727f79ae61d8a889fb9f1928d2d911c807.