Steem
* vests_to_sbd and vests_to_rshares added
* rshares_to_vote_pct let you calculate how many voting percentage are needed  to vote with a desired rshares amount
* app can be set for post, when not set, it is set to beem/version
* Doku improved
Transactionbuilder
* Doku improved
* proposer from __ini__ removed, as it had no function
* _is_signed and _is_constructed fixed
* reconstruct_tx added to sign and addSigningInformation, when set to False, previous signatures are not deleted anymore
* KeyNotFound exception handled
Wallet
* KeyNotFound exception handled, when more than one key_auths are available
Graphenerpc
* version string set to user-agent
Publickey
* Doku improved
Unit tests
test_steem:
* test for test_post improved
* test_sp_to_sbd and test_rshares_to_vote_pct added
tst_testnet:
* test_wallet_keys added  for testing the wallet
* test_transfer_1of1, test_transfer_2of2_simple, test_transfer_2of2_wallet and test_transfer_2of2_serialized_deserialized added thanks to @leprechaun