Draft implementation of block encryption, decryption and key scheduling routines

This version of release includes three implementations versions:

• compact (at compact.c),
• optimised (at optimised.c),
• SIMD (at SIMD.c)

of basic cipher primitives:

• block encryption (encryptBlock),
• block decryption (decryptBlock),
• key scheduling.

Note that encryption and decryption modes in optimised and SIMD versions of implementation require different sets of round keys, the respective set is generated by functions:

• scheduleEncryptionRoundKeys,
• scheduleDecryptionRoundKeys.

All implementation versions are mutually exclusive, and only one version is compiled at a time.