Support for Staking on Block production

[SankaD]

• [x] Tx and Slip Type changes
• [x] Issuance file related changes
• [x] Wallet changes
• [x] Serialization changes
• [x] re org changes
• [x] creating staking transactions
• [x] requiring staked funds when creating blocks
• [ ] when reorganizing, manage staked slips correctly
• [x] add staking slips into issuance file. ( Does locked slips need to mention when they need to be free?)
• [ ] Unit tests on wallet changes
• [ ] Unit tests on serialization changes
• [ ] Unit tests on re org changes
• [ ] Unit tests on staking tx creation
• [ ] Unit tests on block creation with staking transactions