gui: Add logbox to capture page; capture asynchronously
gui: Add logbox to capture page; capture asynchronously

jbaiter/spreads,adongy/spreads,adongy/spreads,DIYBookScanner/spreads,DIYBookScanner/spreads,jbaiter/spreads,gareth8118/spreads,miloh/spreads,miloh/spreads,DIYBookScanner/spreads,nafraf/spreads,nafraf/spreads,jbaiter/spreads,adongy/spreads,gareth8118/spreads,gareth8118/spreads,miloh/spreads,nafraf/spreads