XML Graphics Commons 1.0 replaced with a SVN snapshot (containing the XMP framework).

XML Graphics Commons 1.0 replaced with a SVN snapshot (containing the XMP framework).
Reworked the XMP support for PDF to use the XMP framework from XML Graphics Commons.
XMP metadata embedded in fo:declarations is now properly handled. Its values are copied to the Info object according to the rules from PDF/A-1.
Metadata values from the user agent (title, author etc.) are properly merged with metadata from the XSL-FO document. UserAgent metadata overrides FO metadata.
Note: This is useful and active even if you don't activate PDF/A support.

git-svn-id: https://svn.apache.org/repos/asf/xmlgraphics/fop/trunk@415688 13f79535-47bb-0310-9956-ffa450edef68