add var=val member lookup usable wherver member_id is valid in api commands
add bgimg to layouts with api command or config for global setting
fix bug with overlap layouts combined with odd sized layers
improve switch_img_fit to take a modifier for fit, streach or both at once
function name prefixes from shorthand 'conf' to longer form
'conference'. Also fixes the channel variable names which had been
caught in an over zealous perl -pi -e command...