Expose lamellar running environment (like my_pe) in more general way

[JosephCottam]

my_pe and num_pes are not consistently accessible. Making them consistently accessible enables instrumentation (like a generic lamellar_trace that will print the current PE if known).

Options include:

• Making my_pe and num_pes part of an lamellar_environment trait (or something similar...names are hard) that Lamellar arrays types, teams and world all implement.
• A crate-functions like lamellar_env::my_pe() that can introspect the current running environment.

Candidates for this type of accessibility include the current world identifier, the current team identifier, the current pe identifier and the number of worlds/teams/pes.

[rdfriese]

Implemented a LamellarEnv trait that exposes this functionality (https://github.com/pnnl/lamellar-runtime/commit/fcdfb1dc310fb61bf863b2708532a41ffca6dadb)

below is an example how to use it (and can be found at: https://github.com/pnnl/lamellar-runtime/blob/dev/examples/misc/lamellar_env.rs

/// This example simply showcases the LamellarEnv Trait
use lamellar::array::prelude::*;
use lamellar::darc::prelude::*;
use lamellar::lamellar_env::LamellarEnv;

fn print_env<T: LamellarEnv>(env: &T) {
    println!("my_pe: {}", env.my_pe());
    println!("num_pes: {}", env.num_pes());
    println!("num_threads_per_pe: {}", env.num_threads_per_pe());
    println!("world: {:?}", env.world());
    println!("team: {:?}", env.team());
    println!();
}

fn main() {
    let world = LamellarWorldBuilder::new().build();
    let darc = Darc::new(&world, 0).unwrap();
    let lrw_darc = LocalRwDarc::new(&world, 0).unwrap();
    let grw_darc = GlobalRwDarc::new(&world, 0).unwrap();
    let array = UnsafeArray::<u8>::new(world.clone(), 10, Distribution::Block);
    let team = world
        .create_team_from_arch(StridedArch::new(0, 2, world.num_pes() / 2))
        .unwrap();
    println!("environment from world");
    print_env(&world);
    println!("environment from darc");
    print_env(&darc);
    println!("environment from lrw_darc");
    print_env(&lrw_darc);
    println!("environment from grw_darc");
    print_env(&grw_darc);
    println!("environment from UnsafeArray");
    print_env(&array);
    let array = array.into_atomic();
    println!("environment from AtomicArray");
    print_env(&array);
    let array = array.into_local_lock();
    println!("environment from LocalOnlyArray");
    print_env(&array);
    let array = array.into_global_lock();
    println!("environment from GlobalLockArray");
    print_env(&array);
    if world.my_pe() % 2 == 0 {
        println!("environment from team");
        print_env(&team);
    }
}