Beta version 5.0.0

This major release includes numerous usability and core updates. Existing wallets and ledgers will be invalid so delete the RaiBlocksBeta directory in your home directory on OSX/Linux or in your AppData/Local directory on Windows.

Major changes:

• Changed hashing function to Blake2 for improved performance.
• Block viewer added under advanced in wallet
• Network connection indicator added to wallet.
• You can now switch between wallet accounts
• Configurable logging

Minor changes:

• Wallet key derivation is done in background so startup is more responsive
• cerr logging now shows timestamps
• Bootstrap nodes are chosen randomly from peers instead of always the first one.
• Nodes can send out confirm requests if broadcast voting has ended
• Finding a successor is now constant time instead of O(n) which would have been a DOS vulnerability.
• Merging fork_source with overreceive and calling it unreceivable since they're all the same concept and not really forks.