Beem

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* New UnknownTransaction exception that is raised when using get_transaction with an unkown trx_id
* New function is_transaction_existing which returns false, when a trx_id does not exists
* beempy info does not show information for a trx_id
* broadcast from TransactionBuilder can now return a trx_id, when set trx_id to True (default)
* sign and finalizeOp from Hive and Steem return now the trx_id in a field
* add export parameter to all broadcast commands in beempy
* When setting unsigned in beempy, the default value of expires is changed to 3600
* beempy history returns account history ops in table or stored in a json file

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* fixed missing module in setup.py

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* new beemstorage module
* Config is handled by SqliteConfigurationStore or InRamConfigurationStore
* Keys are handled by SqliteEncryptedKeyStore or InRamPlainKeyStore
* Move aes to beemgraphenebase
* Wallet.keys, Wallet.keyStorage, Wallet.token and Wallet.keyMap has been removed
* Wallet.store has now the Key Interface that handles key management
* Token handling has been removed from Wallet
* Token storage has been move from wallet to SteemConnect/HiveSigner
* handle virtual ops batch streaming fixed thanks to crokkon

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* receiver parameter removed from beempy decrypt
* beempy encrypt / decrypt is able to encryp/derypt a binary file
* encrypt_binary, decrypt_binary and extract_decrypt_memo_data added to beem.memo
* extract_memo_data added to beembase.memo

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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

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* replace asn1 by asn1crypto