added mimetypes required for EPUB documents: .epub (zip), .opf (xml), and .ncx (xml)
added mimetypes required for EPUB documents: .epub (zip), .opf (xml), and .ncx (xml)

opf and ncx are treated as application-specific mimetypes, as listed in http://www.idpf.org/2007/opf/OPF_2.0_final_spec.html#Section2.0 (OPF) and http://www.idpf.org/2007/opf/OPF_2.0_final_spec.html#Section2.4.1.2 (NCX)

Port of revs 11101 and 11102

git-svn-id: 1623499149f5af833cfad2814dce82e821210f6f@11680 8784284e-840f-0410-bd5a-a6a6012a0d1a

orbeon/eXist-1.4.x,kingargyle/exist-1.4.x,orbeon/eXist-1.4.x,orbeon/eXist-1.4.x,kingargyle/exist-1.4.x,kingargyle/exist-1.4.x,kingargyle/exist-1.4.x,kingargyle/exist-1.4.x,kingargyle/exist-1.4.x,orbeon/eXist-1.4.x,orbeon/eXist-1.4.x,orbeon/eXist-1.4.x