Rust 2021 edition has a few improvements over the 2018 edition. Migrate
the project to 2021 edition by following recommended migration steps.
Luckily, the code itself doesn't require fixing.
Bump MSRV to 1.56 as it is required by the 2021 edition. Also fix the
clap build dependency to make Cloud Hypervisor build again.
Signed-off-by: Wei Liu <liuwe@microsoft.com>
This doesn't really affect the build as we ship a Cargo.lock with fixed
versions in. However for clarity it makes sense to use fixed versions
throughout and let dependabot update them.
Signed-off-by: Rob Bradford <robert.bradford@intel.com>
Split out the HTTP request handling code from ch-remote into a new
crate which can be used in other places where talking to the API server
by HTTP is necessary.
Signed-off-by: Rob Bradford <robert.bradford@intel.com>