Minor changes to readme
Minor changes to readme

ravn-no/readium-js,readium/readium-js,bibliolabs/readium-cfi-js,kivuto/readium-js,pmstss/readium-cfi-js,bibliolabs/readium-cfi-js,ravn-no/readium-js,bibliolabs/readium-js,pmstss/readium-cfi-js,readium/readium-js,looknear/readium-js,kivuto/readium-js,readium/readium-cfi-js,bibliolabs/readium-js,looknear/readium-js