Improvements and more unit tests

beem/__init__.py

beem/discussions.py

beem/price.py

beem/steem.py

beem/version.py

beem/wallet.py

beemapi/__init__.py

beemapi/version.py

beemapi/websocket.py

beembase/__init__.py

beembase/version.py

beemgrapheneapi/__init__.py

beemgrapheneapi/grapheneapi.py

beemgrapheneapi/graphenewsrpc.py

beemgrapheneapi/version.py

beemgraphenebase/__init__.py

beemgraphenebase/types.py

beemgraphenebase/version.py

setup.py

tests/__init__.py