Fix character encoding in .properties

java.util.Properties#load(InputStream inStream)  assumes a character encoding of ISO 8859-1, whereas java.util.Properties#load(Reader reader) - or more specifically InputStreamReader(InputStream in) - uses the default encoding.

This simple patch makes Thymeleaf load .properties files in the default encoding, which can also be set by specifying ie. -Dfile.encoding=UTF-8