fix SVG replacement for logo so it works in IE8, fix #7866
specify logo to not repeat when container is bigger
enable SVG->PNG fallback for newly uploaded files and folders
enable SVG->PNG fallback for 'New' menu
fix breadcrumbs for IE8
Merge pull request #7913 from owncloud/fix-logo

fix SVG replacement for logo so it works in IE8, fix #7866