Added peers details to ethcore_netPeers RPC (#2580)

* added peers details to ethcore_netPeers RPC

* fixed build (traits autoimplemented)

* - documentation fixes
- spaces -> tabs
- Rust-way Option's handling

* prepare for new protocols in ethcore_netPeers

* commas & documentation

util/network/src/lib.rs

@@ -99,6 +99,7 @@ pub use host::NetworkIoMessage;
 pub use error::NetworkError;
 pub use host::NetworkConfiguration;
 pub use stats::NetworkStats;
+pub use session::SessionInfo;
 
 use io::TimerToken;
 pub use node_table::is_valid_node_url;