fix nested dichotomous initial values; related to USEPA/BMDS#94 (#91)

Author: shapiromatron

tests/data/db.yaml

@@ -10918,7 +10918,7 @@
                   stdev: 0.0
                   max_value: 18.0
                   min_value: 1.0
-                  initial_value: 0.0
+                  initial_value: 1.0
                 - name: phi
                   type: 0
                   stdev: 0.0
@@ -11578,7 +11578,7 @@
                   stdev: 0.0
                   max_value: 18.0
                   min_value: 1.0
-                  initial_value: 0.0
+                  initial_value: 1.0
                 - name: phi
                   type: 0
                   stdev: 0.0
@@ -12238,7 +12238,7 @@
                   stdev: 0.0
                   max_value: 18.0
                   min_value: 1.0
-                  initial_value: 0.0
+                  initial_value: 1.0
                 - name: phi
                   type: 0
                   stdev: 0.0
@@ -12898,7 +12898,7 @@
                   stdev: 0.0
                   max_value: 18.0
                   min_value: 1.0
-                  initial_value: 0.0
+                  initial_value: 1.0
                 - name: phi
                   type: 0
                   stdev: 0.0