FOP-2312: font-base configuration setting not working as expected
Use the config file URI to resolve relative <base> / <font-base> URIs.
Fall back to default base URI only if the config input stream has no URI.


git-svn-id: https://svn.apache.org/repos/asf/xmlgraphics/fop/trunk@1542190 13f79535-47bb-0310-9956-ffa450edef68