Update toc.ncx
Update toc.ncx

Remove the Doctype (EpubCheck 3.0.1 error).
looknear/readium-js-viewer,NYULibraries/readium-js-viewer,kivuto/readium-js-viewer,cene-co-za/readium-js-viewer,GermanCentralLibraryForTheBlind/readium-js-viewer,becka11y/readium-js-viewer,NYULibraries/readium-js-viewer,mrmayfield/readium,joemerante/readium-js-viewer-firefox,cene-co-za/readium-js-viewer,readium/readium-js-viewer,AndyHubert/readium-js-viewer,readium/readium-js-viewer,mrmayfield/readium,AndyHubert/readium-js-viewer,becka11y/readium-js-viewer,looknear/readium-js-viewer,kivuto/readium-js-viewer,GermanCentralLibraryForTheBlind/readium-js-viewer