message: Update small_panic description
diff: name = "libtock_small_panic"
  authors = ["Tock Project Developers <tock-dev@googlegroups.com>"]
  version = "0.1.0"
  -description = """Default panic handler for libtock. Calls low-level debug on panic and yields."""
  +description = """Small and basic panic handler for libtock. Calls low-level debug on panic and terminates."""
  edition = "2018"
  license = "Apache-2.0 OR MIT"
  repository = "https://www.github.com/tock/libtock-rs"
  