Add Twofish

SpinalHDL -> 1.3.6
SBT -> 1.2.7
Add Twofish algorithm

First release

Add the following algos :

• Symmetric
  • Block Cipher Mode of Operation (BCMO) (ECB, CBC, CFB, OFB)
  • AESCore_Std (128/192/256-bit)
  • DESCore_Std
  • TripleDESCore_Std
• Hash
  • MD5Core_Std
  • SHA2Core_Std
  • SHA3Core_Std
• MAC
  • HMACCore_Std
• Checksum
  • CRC (CRC8, CRC16, CRC32)
• Misc
  • LFSR (Galois & Fibonacci)
  • Keccak

Use SpinaHDL versionl 1.1.6