Fix a couple of typos in the zmqpp source code.

Signed-off-by: Simon Dawson <spdawson@gmail.com>

diff -Nurp a/src/zmqpp/socket.cpp b/src/zmqpp/socket.cpp
--- a/src/zmqpp/socket.cpp	2012-12-11 11:06:23.000000000 +0000
+++ b/src/zmqpp/socket.cpp	2013-03-18 17:32:01.464761776 +0000
@@ -587,7 +587,7 @@ void socket::get(socket_option const& op
 	}
 }
 
-socket::socket(socket&& source) noexcept
+socket::socket(socket& source) noexcept
 	: _socket(source._socket)
 	, _type(source._type)
 	, _recv_buffer()
@@ -601,7 +601,7 @@ socket::socket(socket&& source) noexcept
 	source._socket = nullptr;
 }
 
-socket& socket::operator=(socket&& source) noexcept
+socket& socket::operator=(socket& source) noexcept
 {
 	_socket = source._socket;
 	source._socket = nullptr;
diff -Nurp a/src/zmqpp/socket.hpp b/src/zmqpp/socket.hpp
--- a/src/zmqpp/socket.hpp	2012-12-11 11:06:23.000000000 +0000
+++ b/src/zmqpp/socket.hpp	2013-03-18 17:31:53.556790457 +0000
@@ -400,7 +400,7 @@ public:
 	 *
 	 * \param source target socket to steal internals from
 	 */
-	socket(socket&& source) noexcept;
+	socket(socket& source) noexcept;
 
 	/*!
 	 * Move operator
@@ -413,7 +413,7 @@ public:
 	 * \param source target socket to steal internals from
 	 * \return socket reference to this
 	 */
-	socket& operator=(socket&& source) noexcept;
+	socket& operator=(socket& source) noexcept;
 
 	/*!
 	 * Check the socket is still valid