Merge pull request #105 from mfaber/updatestataexport

DEV: Fixed STATA export: No output when debug!=0
dev: changed width of plugin grid and made layout more compact and bordered
dev: Moved export styles to plugin 
dev: used authdb since that is always enabled, we should move all core plugins that can not be deactivated here to prevent clutter in the plugin screen
dev: still todo: move r and spss here and update remote control
dev: moved plugins to demo so they don't show up and are only available for coders as inspiration since they serve no real purpose
dev: Added housekeeping to pluginmanager -> now missing plugins will be removed from database
Changed feature: Moved R-export to plugin and to normal export responses dialog
dev: a little more compact layout
dev: Fixed error where survey --> answers array not initialized
Fixed issue : Ranking question are not side by side in IE7
Dev: IE7 round up
Dev: I don't see this first time ?
Dev: trying overflow hack too : no way
Fixed issue : caption is visible with IE7
Dev: summary are removed from HTML5, but we're not in HTML5 actually
Dev: For HTML5, seems better to use ARIA-described and ARIA-labeleledby for input
Dev: BUT label inside td can be used to for little screen browser : show whole block
Dev: see Opera mini screenshot at bug #6698