Added model builders (preliminary)
diff --git a/plugins/org.eclipse.app4mc.amalthea.model/META-INF/MANIFEST.MF b/plugins/org.eclipse.app4mc.amalthea.model/META-INF/MANIFEST.MF
index e0c963e..322f1ad 100644
--- a/plugins/org.eclipse.app4mc.amalthea.model/META-INF/MANIFEST.MF
+++ b/plugins/org.eclipse.app4mc.amalthea.model/META-INF/MANIFEST.MF
@@ -6,6 +6,7 @@
 Bundle-ClassPath: .
 Bundle-RequiredExecutionEnvironment: JavaSE-1.8
 Export-Package: org.eclipse.app4mc.amalthea.model,
+ org.eclipse.app4mc.amalthea.model.builder,
  org.eclipse.app4mc.amalthea.model.check,
  org.eclipse.app4mc.amalthea.model.impl,
  org.eclipse.app4mc.amalthea.model.io,