Add details around installation, usage and link to a few talks

This fixes #38

width and height were switched.

During testing I always forget how to use vsock, or virtio-fs.
This commit adds some more detailed examples for the various virtio
devices.

This adds support for `--device rosetta,mountTag=something` on the
commandline. This is only available on system with Apple CPUs, vfkit
will error out if this option is used on Intel CPUs.

Once the VM is running and the rosetta share is mounted, rosetta support can be enabled by creating this file:

$ cat /etc/binfmt.d/rosetta.conf
:rosetta:M::\x7fELF\x02\x01\x01\x00\x00\x00\x00\x00\x00\x00\x00\x00\x02\x00\x3e\x00:\xff\xff\xff\xff\xff\xfe\xfe\x00\xff\xff\xff\xff\xff\xff\xff\xff\xfe\xff\xff\xff:/mnt/rosetta:F

and then running `systemctl restart systemd-binfmt`

See these links for more details:
https://developer.apple.com/documentation/virtualization/running_intel_binaries_in_linux_vms_with_rosetta?language=objc
https://docs.kernel.org/admin-guide/binfmt-misc.html
https://www.man7.org/linux/man-pages/man5/binfmt.d.5.html

This fixes #23

When comparing strings with JSON content, assert.JSONEq is better than
assert.Equal as it will give better output when the 2 strings don't
match, and it tests for equivalence, not strict equality. This means
changes in field order is not a failure for example.

The code was checking for this on all arches, but it's only arm64
kernels which vfkit can't boot if they are compressed.

So far we were using `h2non/filetype` which is not a great fit for what
we want to do, as kernels do not have their own mimetypes, and there is
no nice way to convey compressed/uncompressed/arch through mime types.

This was working through heuristics so far, but the used heuristics
break for the kernel used by puipui linux
(https://github.com/Code-Hex/puipui-linux)

This commit removes the use of h2non/filetype, and reuses the patterns
from https://github.com/file/file/blob/master/magic/Magdir/linux to do
the detection we need.

This only adds a magic for uncompressed arm64 kernels.
There's also a pattern for compressed kernels, but it does not match the arm64
kernels I tested with. They are either detected as gzip files, or as EFI files,
and don't contain the magic pattern.

This ensures both puipui kernel and fedora/RHEL kernels are detected as
uncompressed when they are.

The fix for Code-Hex/vz#131 is not in a tagged
Code-Hex/vz release, but this can trigger crashes in vfkit.
This commit updates Code-Hex/vz to latest git main to get this fix.

This updates all direct go modules to their latest version.

In the previous API, there was no way to detect before changing the
status, which would make it difficult for developers to handle the
following situations:

    - When the virtual machine status is Stop, calling Pause may fail.
    - When the virtual machine status is Pause, setting the status to
      Pause again may fail.

In the previous solution, developers needed to first get the current
status of the virtual machine and then decide whether to proceed to the
next step. However, the current virtual machine status is very diverse
(see:
https://github.com/Code-Hex/vz/blob/bd29a7ea3d39465c4224bfb01e990e8c220a8449/virtualization.go#L23),
which would require developers to handle various cases perfectly. This
PR solves this problem.

This jumps from 0.1.1 to 0.5.0 to better reflect vfkit's maturity.

When ConnectVSockSync fails in watchWakeupNotifications(),
the returned net.Conn contains a nil value, but is not a nil interface
(ie checking it for `== nil` returns false).
This means we'll try to call `Close()` on the connection, which will
cause a nil pointer dereference.
See https://go.dev/doc/faq#nil_error and https://groups.google.com/g/golang-nuts/c/wnH302gBa4I
for details about this behaviour.

This bug is fixed by returning a nil interface when
`vsockDevice.Connect(uint32(port))` returns an error.