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* add participation_rate to Blockchain
* beembase.transactions is deprecated
* get_block_params added to TransactionBuilder
* add Prefix class for PasswordKey, Brainkey, Address, PublicKey, PrivateKey, Base58
* New Class BitcoinAddress
* Address class has now from_pubkey class method
* Message class improved
* beempy message can be used to sign and to verify a message
* decryption of long messages fixed
* varint decoding added to memo decryption
* beempy encrypt / decrypt can be used to encrypt/decrypt a memo text with your memo key