Add a bit more resiliency for unmarshalling

Ref: https://s3-us-west-2.amazonaws.com/cloudformation-templates-us-west-2/WordPress_Multi_AZ.template

func_select.go

@@ -1,6 +1,9 @@
 package cloudformation
 
-import "encoding/json"
+import (
+	"encoding/json"
+	"fmt"
+)
 
 type selectArg interface{}
 
@@ -47,9 +50,26 @@ func (f *SelectFunc) UnmarshalJSON(data []byte) error {
 	if len(v.FnSelect) != 2 {
 		return &json.UnsupportedValueError{Str: string(data)}
 	}
-	if err := json.Unmarshal(v.FnSelect[0], &f.Selector); err != nil {
+	// Possible that the second arg is another template, in which case
+	// we need to check for that...Example:
+	/*
+		"Fn::Select": [
+				0,
+				{
+						"Fn::GetAtt": [
+								"ApplicationLoadBalancer",
+								"SecurityGroups"
+						]
+				}
+		]
+	*/
+	var positionSelector interface{}
+	if err := json.Unmarshal(v.FnSelect[0], &positionSelector); err != nil {
 		return err
 	}
+	f.Selector = fmt.Sprintf("%v", positionSelector)
+
+	// What about the second one?
 	if err := json.Unmarshal(v.FnSelect[1], &f.Items); err != nil {
 		return err
 	}

string_list.go

@@ -62,6 +62,13 @@ func (x *StringListExpr) UnmarshalJSON(data []byte) error {
 			x.Func = stringFunc
 			return nil
 		}
+
+		// Possible that it's a Fn::GetAtt instance?
+		getAttrFunc, ok := funcCall.(GetAttFunc)
+		if ok {
+			x.Func = StringList(getAttrFunc)
+			return nil
+		}
 		return fmt.Errorf("%#v is not a StringListFunc", funcCall)
 	}