v0.2.0: cargo: prepare for 0.2.0 release

[v0.2.0]

Added

• Enhance passthrough to reduce active fds by using file handle
• implement Fromfusedev::Error for std::io::Error
• Use vhost crate from crates.io
• Introduce readlinkat_proc_file helper
• Update vm-memory to 0.7.0
• Add @eryugey to CODEOWNERS file

Fixed

• Validate path components
• Prevent ".." escape in do_lookup in passthroughfs
• Prevent opening of special file in passthroughfs
• Fix compile error in vfs async test
• Record real root inode's ino of file system backends in vfs

Deprecated