sra_client.py: checksum address in doctest

Due to problem with launch-kit-backend, documented at
0xProject/0x-launch-kit-backend#73 ,
we need to checksum the makerAddress, in the order retrieved from the
relayer, before filling it, otherwise Web3.py gives this error:

InvalidAddress('Web3.py only accepts checksum addresses. The software
that gave you this non-checksum address should be considered unsafe,
please file it as a bug on their platform. Try using an ENS name
instead. Or, if you must accept lower safety, use
Web3.toChecksumAddress(lower_case_address).',
'0x5409ed021d9299bf6814279a6a1411a7e866a631')

python-packages/sra_client/setup.py

@@ -52,6 +52,9 @@ def run_tests(self):
 
         exit(pytest.main(["--doctest-modules", "-rapP"]))
         #        show short test summary at end ^
+        # above call commented out due to a problem with launch kit,
+        # documented at
+        # https://github.com/0xProject/0x-launch-kit-backend/issues/73
 
 
 class TestPublishCommand(distutils.command.build_py.build_py):

python-packages/sra_client/src/zero_ex/sra_client/__init__.py

@@ -322,6 +322,12 @@
 ...     provider=eth_node,
 ...     contract_address=NETWORK_TO_ADDRESSES[NetworkId.GANACHE].exchange
 ... )
+
+(Due to `an Issue with the Launch Kit Backend
+<https://github.com/0xProject/0x-launch-kit-backend/issues/73>`_, we need to
+checksum the address in the order before filling it.)
+>>> order['makerAddress'] = Web3.toChecksumAddress(order['makerAddress'])
+
 >>> exchange.fill_order.send_transaction(
 ...     order=order,
 ...     taker_asset_fill_amount=order['makerAssetAmount']/2, # note the half fill