SHA-3 implementation

[teobiton]

Breakdown into major steps to keep track of advancement for SHA-3 algorithm:

• Software model
• Software model tests
• CI update to run checks on SHA-3 model
• RTL design of top-level and algorithm
• cocotb tests for SHA-3 algorithm
• CI update to run checks on SHA-3 RTL code

Additionally documentation for the algorithm will need to be imported.