Small changes to non-blocking and attachment.

	Originally committed 2014-08-22

src/e-server:
	* src/GdbServer.cpp (GdbServer::rspQuery): Report we are attaching
	to an existing process.
	* src/RspConnection.cpp (RspConnection::getRspChar): Zero length
	return is failure even if non-blocking.

Conflicts (resolved):
	src/e-server/ChangeLog