Improve layout. The layout is now simple and flat.

git-svn-id: http://svn.code.sf.net/p/openmediavault/code/trunk@1135 3c3d7b80-5828-415e-9f61-280b98178fff
Save tree state.

git-svn-id: http://svn.code.sf.net/p/openmediavault/code/trunk@1136 3c3d7b80-5828-415e-9f61-280b98178fff