Sneyd model updates (#285)

* sneyd model, add datasetId column and visualization specification

* fix simulation mixup

* visualization specification

Author: plakrisenko

Benchmark-Models/Sneyd_PNAS2002/Sneyd_PNAS2002.yaml

@@ -8,4 +8,6 @@ problems:
   observable_files:
   - observables_Sneyd_PNAS2002.tsv
   sbml_files:
-  - model_Sneyd_PNAS2002.xml
+  - model_Sneyd_PNAS2002.xml
+  visualization_files:
+  - visualizationSpecification_Sneyd_PNAS2002.tsv