Rework of filesystem info and space update after refresh and file operation. Part of cleaning VFS
BUG: 374404
VFS: cleaning inheritance issues with VFS classes. Part of cleaning VFS
The bug report https://bugs.kde.org/show_bug.cgi?id=374404 made me notice some flaws with the current file space refresh. I couldn't help myself and changed most of the code.
Behaviour changes:
- free space update should work now flawless. I.e. if changes to the filesystem space are made inside Krusader all panels (and tabs) showing the same filesystem are updated
- no special label for /etc and /proc anymore. I feel its fine to show "0 of of 0 bytes" here. And /sys was missing anyway.
- "Virtual Filesystem" is shown now if "virt_fs" is used (and no search meta information is present).