LES Peer Info (#4195)

* connected peers function for network service

* get LES peer info in sync API

* new peer info in RPC

ethcore/light/src/net/context.rs

@@ -77,7 +77,7 @@ impl<'a> IoContext for NetworkContext<'a> {
 	}
 }
 
-/// Basic context for a the protocol.
+/// Basic context for the protocol.
 pub trait BasicContext {
 	/// Returns the relevant's peer persistent Id (aka NodeId).
 	fn persistent_peer_id(&self, peer: PeerId) -> Option<NodeId>;