New-style checkboxes lost again in some places

[jancborchardt]

Where did they go @Henni @owncloud/designers? ;)

Sharing admin settings cc @schiesbn

Notification settings (bottom two checkboxes) cc @nickvergessen

[nickvergessen]

For milestones and sev labels please ask cml to set them.

This is also not a regression, but an incomplete fix. But at least they work, so it's not that critical.

[MorrisJobke]

Where did they go @Henni @owncloud/designers? ;)

They are now opt-in ;)