get the list of server names (blocking)
function () {
			var self = this;
			console.log('getting servers...');
			var req = get_req();
			var server_names;
			req.onreadystatechange = function get_servers_response () {
				if (req.readyState === 4) {
					server_names = JSON.parse(req.responseText);
				}
			};
			req.open("GET", "/servers", false);
			req.send("");
			return server_names;
		}