Use interface supporting pyethereum

Use ethereum/pyethereum#737

Author: LefterisJP

requirements.txt

@@ -5,13 +5,14 @@ pysha3
 git+https://github.com/LefterisJP/pyethapp@raiden_pyethapp_fork#egg=pyethapp
 # temporary until pystun creates a new release
 git+https://github.com/konradkonrad/pystun@develop#egg=pystun
+# temporary until new version of pyethereum is released, that supports interfaces
+git+https://github.com/LefterisJP/pyethereum@take_solidity_interface_into_account#egg=ethereum
 ipython<5.0.0
 rlp>=0.4.3
 coincurve==4.5.1
 pycryptodome>=3.4.3
 miniupnpc
 networkx
-ethereum>=1.6.1
 ethereum-serpent
 repoze.lru
 gevent-websocket==0.9.4

setup.py

@@ -49,6 +49,7 @@ def run(self):
 
 install_requires_replacements = {
     "git+https://github.com/LefterisJP/pyethapp@raiden_pyethapp_fork#egg=pyethapp": "pyethapp",
+    "git+https://github.com/LefterisJP/pyethereum@take_solidity_interface_into_account#egg=ethereum": "ethereum",
     "git+https://github.com/LefterisJP/pyelliptic@make_compatible_with_openssl1_1#egg=pyelliptic": "pyelliptic",
     "git+https://github.com/konradkonrad/pystun@develop#egg=pystun": "pystun",
 }