gui: Added lens alignment tool menu
gui: image optimalisation
gui slider: ensure the cursor is standard when disabled
gui stream entry: add low/high entries to histogram
andorcam2: improve image from fake camera

spread better the greyscale values
dataio tiff: fix loading non OME tiff
gui: display histograms with logarithmic scales
andorcam2: use real raw CCD picture for fake camera
gui: some additional comments/TODOs