Maintainers feel (and I agree) that there's no point in explicitly
allowing a null value when callers can simply leave the property unset
[1]. This commit removes all references to "pointer" and "null" from
the JSON Schema to support that decision. While optional properties
may sometimes be represented as pointer types in Go [2], optional
properties should be represented in JSON Schema by not including the
properties in the 'required' array.
[1]: https://github.com/opencontainers/runtime-spec/pull/555#issuecomment-272020515
[2]: style.md "Optional settings should not have pointer Go types"
Signed-off-by: W. Trevor King <wking@tremily.us>
W. Trevor King
John Howard