Convert test_runtime.sh into a go program

[mrunalp]

No description provided.

[liangchenye]

The similar go implementation is here:
https://github.com/huawei-openlab/oct/blob/master/validate.go
But that is designed for testing multiple cases.
I'd like to prepare a single-case one based on your test_runtime.sh and the change in #7 .

I have a question, where should we put the new program to?
It is higher level of the current ocitools.

[mrunalp]

@liangchenye We can have a program here that takes a path to a rootfs and a test case to start with.

[liangchenye]

The go program is here: https://github.com/liangchenye/ocitools/blob/master/testRuntime.go which is made from oct/validate.go. The command line is not supported yet. Should it became a part of main.go?

[mrunalp]

@liangchenye Nice! I think it should be a part of main.go. There is a validate which I intended for spec validation. Maybe --runtime or a separate command for runtime validation.

[liangchenye]

@mrunalp new PR submitted.
That is used to verify if a bundle was valid. The code was modified from bundleValidator in OCT.
I think it is the 'spec validation' right?

Once the hashing and the archival format are defined in OCI, the relevant codes will also be added to bundle.go.