marcocg: Added following features:
*Account - Account creation, key generation and accessors.
*Transaction - Transaction creation, Sign, Verify and Accessors.
*Miner - Added unit test in main for transaction and accounts
*Block - Moved code from Transaction to generate inputs and outputs for a transaction. Commented out as it needs refactoring.
marcocg: These are the changed I introduce.
*Added Transaction.amount field to the digital signature.
*Changed the assumed encoding of strings containing the keys to be base64 in the Account constructors and methods that use string.
Merge Conflicts