types: Be more lenient on Date, Int, and Amount parsing

Some of these types can have stray newlines in them, and Vanguard has a
very strange bug where they repeat the time portion of a DTSTART element
for a second time (we disregard the latter portion).

types.go

@@ -14,6 +14,25 @@ import (
 
 type Int int64
 
+func (i *Int) UnmarshalXML(d *xml.Decoder, start xml.StartElement) error {
+	var value string
+
+	err := d.DecodeElement(&value, &start)
+	if err != nil {
+		return err
+	}
+
+	value = strings.TrimSpace(value)
+
+	i2, err := strconv.ParseInt(value, 10, 64)
+	if err != nil {
+		return err
+	}
+
+	*i = Int(i2)
+	return nil
+}
+
 type Amount big.Rat
 
 func (a *Amount) UnmarshalXML(d *xml.Decoder, start xml.StartElement) error {
@@ -25,6 +44,8 @@ func (a *Amount) UnmarshalXML(d *xml.Decoder, start xml.StartElement) error {
 		return err
 	}
 
+	value = strings.TrimSpace(value)
+
 	// The OFX spec allows the start of the fractional amount to be delineated
 	// by a comma, so fix that up before attempting to parse it into big.Rat
 	value = strings.Replace(value, ",", ".", 1)
@@ -63,6 +84,9 @@ func (od *Date) UnmarshalXML(d *xml.Decoder, start xml.StartElement) error {
 		return err
 	}
 
+	value = strings.SplitN(value, "]", 2)[0]
+	value = strings.TrimSpace(value)
+
 	// Split the time zone off, if any
 	split := strings.SplitN(value, "[", 2)
 	if len(split) == 2 {