Upgrade RLP dependency

Author: cburgdorf

setup.py

@@ -15,8 +15,8 @@
         "mypy_extensions>=0.4.1,<1.0.0",
         "py-ecc>=1.4.7,<5.0.0",
         "pyethash>=0.1.27,<1.0.0",
-        "rlp==2.0.0-alpha.1",
-        "trie==2.0.0-alpha.4",
+        "rlp>=2,<3",
+        "trie==2.0.0-alpha.5",
     ],
     # The eth-extra sections is for libraries that the evm does not
     # explicitly need to function and hence should not depend on.