transports, api: use new timer methods

transports should call success / failure.
api should call cancel

lib/server/api/delete_timer.js

@@ -9,7 +9,7 @@ module.exports = {
   ]
 , handler: (req, res, node, cb) => {
     const id = req.$.params.timer_id;
-    req.$.timers.remove(id, (err) => {
+    req.$.timers.cancel(id, (err) => {
       if( err ) {
         switch(err.code) {
           case 'ENOENT':

lib/transports/http.js

@@ -39,7 +39,7 @@ module.exports = function httpTransport( method, url, payload, id, cache ) {
   if( method_exp.test(method) && typeof request[_method] !== 'function' ) {
     const t = cache.get(id);
     t && clearTimeout(t.timer);
-    cache.remove(id);
+    cache.failure(id, err);
     debug('unable to execute http transport', method, id);
     return;
   }
@@ -48,17 +48,17 @@ module.exports = function httpTransport( method, url, payload, id, cache ) {
   request[_method](url, options, (err, res, body) => {
     if(err){
       debug('timer err', err);
-      return cache.remove(id);
+      return cache.failure(id, err);
     }
     if(res.statusCode > 299 ){
       debug('timer fail', res.statusCode, body);
       const er = new Error(STATUS_CODES[res.statusCode]);
       er.code = res.statusCode = res.statusCode;
       console.error(er, body);
-      return cache.remove(id);
+      return cache.failure(id, err);
     }
 
     debug('timer sucess');
-    return cache.remove(id);
+    return cache.success(id);
   });
 };