0.2.1 Release 0.2.1

https://www.steemimg.com/images/2016/08/04/steem2fe43.png

New:

• [transactions] Set_withdraw_vesting_route
• [account] properly create a graphene-inherited account module for key related stuff
• [deps] Reduce minimum required dependencies and raise Exceptions for optional dependencies
• [transactions] add account_update_operation
• [init] Also load PasswordKey by default
• [exchange] Added returnOpenOrders and returnBalances logic

Fixes:

• [docs] proper dependencies for readthedocs
• [transactions] do not add virtual operations after all
• [typo] fix typo
• [transactions] fix is_canonical as it takes a signature and not a compact signature
• [exchange] add comments to riverhead's updates
• [secp256k1] make sure signatures are canonical

Remarks:

• If you used to load PrivateKey, PublicKey or similar classes from steembase directly, you
  wil need to replace
  from steembase import ....
  by
  from steembase.account import ....