Improve armem prediction interface

Closes #99 (closed)

Improves the infrastructure for armem predictions.

This MR's branch is based on the linear-prediction branch, so that should be merged first.

source/RobotAPI/components/armem/server/ExampleMemory/ExampleMemory.cpp

@@ -73,7 +73,7 @@ namespace armarx
         workingMemory().addCoreSegment("LinkedData", armem::example::LinkedData::ToAronType());
 
         // We support the "Latest" prediction engine for the entire memory.
-        workingMemory().predictionEngines().push_back({"Latest"});
+        workingMemory().addPredictionEngine({"Latest"});
 
         // For illustration purposes, we add more segments (without types).
         bool trim = true;