EXPERIMENTAL: Remove seemingly unused code.

I couldn't find any tests or documentation that use this code branch, and the
purpose isn't clear to me (why would you pass in a field object as a value?).
It's a small performance gain to just remove it, but if anyone depends on it,
it could be added back.

src/active_record/main.js

@@ -490,10 +490,6 @@ ActiveRecord = {
                 if(!this.constructor.fields[key].primaryKey)
                 {
                     var value = ActiveRecord.connection.fieldOut(this.constructor.fields[key],this.get(key));
-                    if(Migrations.objectIsFieldDefinition(value))
-                    {
-                        value = value.value;
-                    }
                     //don't supress notifications on set since these are the processed values
                     this.set(key,value);
                 }