Update assumed RPC version

Author: petertodd

README.md

@@ -11,7 +11,7 @@ focus on providing tools to manipulate the internals of how Bitcoin works.
 
     sudo apt-get install libssl-dev
 
-The RPC interface, bitcoin.rpc, is designed to work with Bitcoin Core v0.13.0
+The RPC interface, bitcoin.rpc, is designed to work with Bitcoin Core v0.15.0
 Older versions may work but there do exist some incompatibilities.
 
 

bitcoin/rpc.py

@@ -297,7 +297,7 @@ class Proxy(BaseProxy):
     Unlike ``RawProxy``, data is passed as ``bitcoin.core`` objects or packed
     bytes, rather than JSON or hex strings. Not all methods are implemented
     yet; you can use ``call`` to access missing ones in a forward-compatible
-    way. Assumes Bitcoin Core version >= v0.13.0; older versions mostly work,
+    way. Assumes Bitcoin Core version >= v0.15.0; older versions mostly work,
     but there are a few incompatibilities.
     """