updated readme
updated readme

dalbymodo/universalviewer,WSULib/universalviewer,britishlibrary/UniversalViewer,britishlibrary/UniversalViewer,WSULib/universalviewer,dalbymodo/universalviewer,dalbymodo/universalviewer,dalbymodo/universalviewer,dalbymodo/universalviewer,WSULib/universalviewer,WSULib/universalviewer,dalbymodo/universalviewer,WSULib/universalviewer,britishlibrary/UniversalViewer,britishlibrary/UniversalViewer,WSULib/universalviewer,britishlibrary/UniversalViewer,britishlibrary/UniversalViewer