Add examples in documentation

[ionut-arm]

At the moment our documentation is purely comment-based and should be enhanced with some working examples of how to use the functionality within.

[genofire]

Here a little example to get a random byte:

#[macro_use]
extern crate log;

use tss_esapi::Context;
use tss_esapi::Tcti;

fn main() {
    //let env = Env::default().filter_or("LOG_LEVEL", "warn")
    env_logger::init();

    let tpm_ctx_result = unsafe { Context::new(Tcti::Tabrmd) };
    if tpm_ctx_result.is_err() {
        error!("Connection to TPM not established: {}", tpm_ctx_result.unwrap_err());
        return;
    }
    let mut tpm_ctx = tpm_ctx_result.unwrap();

    let random = tpm_ctx.get_random(1);
    if random.is_err() {
        error!("Testing TPM, not able to get_random: {}", random.unwrap_err());
        return;
    }

    info!("Testing TPM, by get_random a byte: {}", random.unwrap()[0]);
}

[hug-dev]

Hi @genofire !
Thanks for the snippet 😃 Would you like to submit a PR that adds this example?
I think for examples it is fine not to have logging and unwrap errors directly, it might simplify your snippet, if you agree.

[genofire]

It will take some time (days), for me it is more importent to work with Quote (and as first step with PCR) - but i could do it ... where should it be ? in README or somewhere else?

[hug-dev]

A good place to put it would be in the code documentation of the get_random function, here. That way it will show in our docs.rs documentation!
Below the # Errors section you can add an # Example section as explained here. You will probably need to put the no_run attribute on that block to only compile the example whe ntests are executed.
cargo test --doc should try to compile the example to check if it works 😃

[hug-dev]

We should target putting docs on all public items + example on main methods.