Update licensing information

Dependencies

• [2] F245RKAI Add REUSE-compliant licensing information
• [3] YDK6X6PP add a library of important types for beancount
• [4] 2JBFREZG enable additional warnings
• [5] WS3UUOV3 Extract commodity type into separate crate

Change contents

• replacement in beancount/commodity/tests/basic.rs at line 1
  [3.43]→[2.0:53](∅→∅)
  − // SPDX-FileCopyrightText: 2023 Markus Haug (Korrat)
  [3.43]

  [2.53]
  + // SPDX-FileCopyrightText: 2023 - 2024 Markus Haug (Korrat)
• replacement in beancount/commodity/src/lib.rs at line 1
  [3.8128]→[3.1955:2012](∅→∅),[3.2012]→[2.95:149](∅→∅)
  − #![warn(clippy::all, clippy::nursery, clippy::pedantic)]

  −

  − // SPDX-FileCopyrightText: 2023 Markus Haug (Korrat)
  [3.8128]

  [2.149]
  + // SPDX-FileCopyrightText: 2023 - 2024 Markus Haug (Korrat)
• edit in beancount/commodity/src/lib.rs at line 4
  [2.189]

  [3.2012]
  +

  + #![warn(clippy::all, clippy::nursery, clippy::pedantic)]
• replacement in beancount/commodity/Cargo.toml at line 1
  [3.1084]→[2.190:242](∅→∅)
  − # SPDX-FileCopyrightText: 2023 Markus Haug (Korrat)
  [3.1084]

  [2.242]
  + # SPDX-FileCopyrightText: 2023 - 2024 Markus Haug (Korrat)