Add assert-message (#1386)

Author: dbinkele

code/languages/org.iets3.opensource/languages/org.iets3.analysis.base/models/plugin.mps

@@ -5146,6 +5146,20 @@
     </node>
     <node concept="2uRRBT" id="2f_Mi5n7Ldo" role="2uRRB$">
       <node concept="3clFbS" id="2f_Mi5n7Ldp" role="2VODD2">
+        <node concept="3clFbF" id="2F3xlwaQIEB" role="3cqZAp">
+          <node concept="2OqwBi" id="2F3xlwaQIE$" role="3clFbG">
+            <node concept="10M0yZ" id="2F3xlwaQIE_" role="2Oq$k0">
+              <ref role="1PxDUh" to="wyt6:~System" />
+              <ref role="3cqZAo" to="wyt6:~System.out" />
+            </node>
+            <node concept="liA8E" id="2F3xlwaQIEA" role="2OqNvi">
+              <ref role="37wK5l" to="guwi:~PrintStream.println(java.lang.String)" resolve="println" />
+              <node concept="Xl_RD" id="2F3xlwaQIK7" role="37wK5m">
+                <property role="Xl_RC" value="-------&gt; SolverCheck" />
+              </node>
+            </node>
+          </node>
+        </node>
         <node concept="3clFbF" id="2f_Mi5n7QNu" role="3cqZAp">
           <node concept="37vLTI" id="2f_Mi5n7Rqk" role="3clFbG">
             <node concept="2OqwBi" id="2f_Mi5n7QXY" role="37vLTJ">