add a check and a warning if the ownClodu server is not able to establish http connections to the internet. The reason is that users complained that external filesystem support, the update checker, downloading of new apps or the nowledgebase don´t work and don´t know why.

CSS typo fixed.

Remove sharing notice in users settings - The default is now share with anyone, groups only sharing is now a setting in the admin page

Conflicts:

	settings/css/settings.css

Per user quota didn't show in FF (and possibly IE) http://forum.owncloud.org/viewtopic.php?f=4&t=2716&p=5373#p5324.

show a label if an app is an internal app or a third party app from the app store.
show a preview image of the app if available