Current `[a-z_]+` regex allows upper case such as `NET_dev`, `netDev`
or even `NET_DEV` when one of `a-z` or `_` contains in the string. It
should be disallowed.
This patch fixes it.
User may specify a program_type by prompt or CLI flag.
We then generate skeleton code to the ebpf program for a noop program of
that type.
Requires cargo-generate@main
Signed-off-by: Dave Tucker <dave@dtucker.co.uk>