Configure inner math field with options

When finalizeTree() is called for inner math fields, it takes an
options object as a parameter. This object was not actually used to
configure the inner math field. This change ensures inner math fields
are configured correctly with the passed options.
diff --git a/src/commands/math/commands.js b/src/commands/math/commands.js
index 51e712a..8f12745 100644
--- a/src/commands/math/commands.js
+++ b/src/commands/math/commands.js
@@ -782,8 +782,8 @@
       .map(function(name) { self.name = name; }).or(succeed())
       .then(super_.parser.call(self));
   };
-  _.finalizeTree = function() {
-    var ctrlr = Controller(this.ends[L], this.jQ, Options());
+  _.finalizeTree = function(options) {
+    var ctrlr = Controller(this.ends[L], this.jQ, options);
     ctrlr.KIND_OF_MQ = 'MathField';
     ctrlr.editable = true;
     ctrlr.createTextarea();