Fix install command in docs

[erikreppel]

Motivation

➜  cryo git:(main) cargo install --path .
error: found a virtual manifest at `/Users/erikreppel/dev/cryo/Cargo.toml` instead of a package manifest

Install command in README fails

Solution

Install the cli directly

➜  cryo git:(main) cargo install --path ./crates/cli 
  Installing cryo_cli v0.1.0 (/Users/erikreppel/dev/cryo/crates/cli)
    Updating crates.io index
  Downloaded byte-slice-cast v1.2.2
  Downloaded phf_macros v0.11.2
  Downloaded bytemuck v1.13.1
  ...
  Installing /Users/erikreppel/.cargo/bin/cryo
   Installed package `cryo_cli v0.1.0 (/Users/erikreppel/dev/cryo/crates/cli)` (executable `cryo`)
➜  cryo git:(main) cryo
error: the following required arguments were not provided:
  <DATATYPE>...

Usage: cryo <DATATYPE>...

For more information, try '--help'.

PR Checklist

• Added Tests
• Added Documentation
• Breaking changes

[sslivkoff]

great thanks