::VFS::Uri: bug fix
 - parsing of file:// schema.
Add ::VFS::IFileContainer::schema.
Add ::VFS::SelfContainedSnapshotItem.
Add PScopedPointer::reset.
Add ::VFS::Plugins::Default::InvalidInfo.
::Tools::Memory::Holder:
 - add overloaded operator=.
::Tools::Settings::Container:
 - remove extra debug include.
Add PScopedPointer::const_data method.
::VFS::Plugins::Default: new feature
 - copy through clipboard.