Restructure into VRTRun/VRTRunserver and VRTStatistics

[jackjansen]

To implement cwi-dis/VR2Gather#205 we have to split this repo into two separate packages (or maybe three?)

• VRTRun and VRTRunserver handle the remote execution of VR2Gather experiences, plus copying the config files and the results. Basically the current VRTStatistics-runserver and half of VRTStatistics-ingest
• VRTStatistics handles all the rest, which is basically the data processing, querying, graphing.

The advantage of this is that VRTRunserver will have few dependencies, and none of the numpy and script and all of that, which makes it a lot easier to include it into the built VR2Gather player.