in `./bins/inbreeding/`, this MR does
- refactor the "list item drawing" from `environment.rs` and `strategy.rs` into the `draw_unique_elements` function of new `random.rs` module
- use a `HashSet` to draw unique indices in the slice of "things" to draw from and then extracts the items corresponding to these indices

## results
```bash
use ./bins/inbreeding
use std bench

const PRNG_SEED = 0
const OPTS = {
    nb_bytes: (10 * 1_024),
    k: 10,
    n: 20,
    nb_measurements: 100,
    nb_scenarii: 10,
    measurement_schedule: 1,
    measurement_schedule_start: 2_000,
    max_t: 2_000,
    strategies: [ "single:5" ],
    environment: null,
}

def run [rev: string] {
    git co $rev

    inbreeding build

    let a = bench --rounds 5 {
        inbreeding run --options ($OPTS | update environment "fixed:0") --prng-seed $PRNG_SEED
    }
    let b = bench --rounds 5 {
        inbreeding run --options ($OPTS | update environment "fixed:1") --prng-seed $PRNG_SEED
    }

    {
        0: $a,
        1: $b,
    }
}

let main = run a29b511d
let mr = run fix-shuffle
```
```bash
let table = [
    [env, main, mr, improvement];

    ["fixed:0", $main."0".mean, $mr."0".mean, (($main."0".mean - $mr."0".mean) / $main."0".mean * 100)],
    ["fixed:1", $main."1".mean, $mr."1".mean, (($main."1".mean - $mr."1".mean) / $main."1".mean * 100)],
]

$table | to md --pretty
```

| env     | main                    | mr                      | improvement        |
| ------- | ----------------------- | ----------------------- | ------------------ |
| fixed:0 | 8sec 504ms 794µs 784ns | 6sec 353ms 206µs 645ns | 25.298530930431912 |
| fixed:1 | 727ms 648µs 292ns      | 639ms 443µs 782ns      | 12.12186037811795  |

the improvement is quite nice, even though not huge, but the code is cleaner anyways 🙏

this adds `$.diversity.e` to the output of `inbreeding load` and input of `inbreeding plot` to show errors bars in the final plot.

these can be discarded by running something similar to
```bash
inbreeding load $experiment
    | reject diversity.e
    | inbreeding plot --options { k: $OPTS.k }
```

plotting "inbreeding" results is now done in two steps
- `load` the data from raw experiment files with `inbreeding load`
- `plot` the results by piping this data into `inbreeding plot`

## new structure for the repository
- benchmarks are in `./benchmarks/` and can be run with either `cargo run --package benchmarks --bin <bench>` or the commands in `./benchmarks/README.md`
```
├── Cargo.toml
├── README.md
└── src
    └── bin
        ├── commit.rs
        ├── fec.rs
        ├── linalg.rs
        ├── operations
        │   ├── curve_group.rs
        │   └── field.rs
        ├── recoding.rs
        ├── setup.rs
        └── setup_size.rs
```

- examples are now in `./bins/` as standalone binaries and can be run either with `cargo run --package <pkg>` or with the help of the `cargo bin` command from `.nushell/cargo.nu`
```
├── curves
│   ├── Cargo.toml
│   ├── README.md
│   └── src
│       └── main.rs
├── inbreeding
│   ├── build.nu
│   ├── Cargo.toml
│   ├── consts.nu
│   ├── mod.nu
│   ├── plot.nu
│   ├── README.md
│   ├── run.nu
│   └── src
│       ├── environment.rs
│       ├── main.rs
│       └── strategy.rs
├── rank
│   ├── Cargo.toml
│   └── src
│       └── main.rs
└── rng
    ├── Cargo.toml
    └── src
        └── main.rs
```

- Nushell modules are now located in `./.nushell/`

## changelog
apart from the changes to the general structure of the repo:
- `binary.nu` -> `.nushell/binary.nu`
- new `cargo bin` command from `.nushell/cargo.nu`
- `error throw` is now defined in `.nushell/error.nu`
- main TOML has been greatly simplified because the dependencies of "examples" have been moved to the associated crates
- the rest is basically the same but in the new structure