Implement delegate registration command for DPoS module

[mehmetegemen]

Description

Implement delegate registration command in delegate_registration.ts in the commands folder as in the LIP (https://research.lisk.com/t/define-state-and-state-transitions-of-dpos-module/320#delegate-registration-42)

• Define command id and schema as in the LIP
• Define command name as registerDelegate
• Implement verify hook as in the LIP
• Implement execute hook as in the LIP

Acceptance Criteria

• Possible scenarios are tested in the unit test for hooks