Made symboliclog depend on imagecapturer

Right now, the system would block if an image is to be captured when no imagecapturer is loaded. This fixes that for now.
Added ArbitraryMappingsHolder intermediate class

The class will hold arbitrary static configuration data, to be saved in arbitrary mapping files. These are configurable through the main config.cfg file per plugin. Also, cleaned up the linking mechanism to make linking new components easier and clearer.
Only predict when a model was loaded

The prediction plugin would return errors when trying to predict without a model present. This fix circumvents this and ignores all prediction requests when no model is present, returning SUCCESS on all occasions (i.e. no failures).