graph query exceeeds param limit

node.js has some built-in http header limit. when this gets exceeded,
it terminates the connection and all the queued queries fail as well

src/js/client.js

@@ -1440,22 +1440,34 @@ angular.module('Application').service('Client', ['$http', '$interval', '$timeout
     };
 
     Client.prototype.graphs = function (targets, from, options, callback) {
-        var config = {
-            params: {
-                target: targets,
-                format: 'json',
-                from: from
-            }
-        };
+        // if we have a lot of apps, targets can be very large. node will just disconnect since it exceeds header size
+        var size = 10, chunks = [];
+        for (var i = 0; i < targets.length; i += size) {
+            chunks.push(targets.slice(i, i+size));
+        }
 
-        if (options.noNullPoints) config.params.noNullPoints = true;
+        var result = [];
+        asyncForEach(chunks, function (chunk, iteratorCallback) {
+            var config = {
+                params: {
+                    target: chunk,
+                    format: 'json',
+                    from: from
+                }
+            };
 
-        get('/api/v1/cloudron/graphs', config, function (error, data, status) {
-            if (error) return callback(error);
-            if (status !== 200) return callback(new ClientError(status, data));
+            if (options.noNullPoints) config.params.noNullPoints = true;
 
-            // the datapoint returned here is an [value, timestamp]
-            callback(null, data);
+            get('/api/v1/cloudron/graphs', config, function (error, data, status) {
+                if (error) return iteratorCallback(error);
+                if (status !== 200) return iteratorCallback(new ClientError(status, data));
+
+                // the datapoint returned here is an [value, timestamp]
+                result = result.concat(data);
+                iteratorCallback(null);
+            });
+        }, function iteratorDone(error) {
+            callback(error, result);
         });
     };