Incremental diagram pieces do not correctly calculate their layout #232
Description
The incremental diagram generation via diagram pieces does not work correctly anymore. The piece requests and communication still work, but the layout call on the server does always put 0/0 coordinates and 0 width/height on every element, resulting in a broken diagram. I did not find the culprit yet while digging a little, just that it seems to have happened somewhere between release 3.0.1 and the current master of KLighD.