Added *Metadata reader for images.*
Modified *At startup, images won't be loaded completly anymore to get metadata like alpha etc. Instead, only metadata will be read. This took down loading time from 22s to 8s*
Modified *Scrolling will not fire a mainImage change imediatly, but instead will wait a given time (0,6s). If no new change has happend, the Scroller informs listener of change. This speeds up scrolling a lot*