message: Elaborate on the meaning of dependency.
diff: @@ -2,7 +2,9 @@ Third Party Dependencies
  ========================
  This document is about dependencies that are required to build applications
  -using `libtock-rs`. Dependencies required to run `libtock-rs`' tests (such as
  +using `libtock-rs`. These dependencies are not contained in the libtock-rs
  +repository, but are used by libtock-rs when libtock-rs is used as a dependency
  +of an application. Dependencies required to run `libtock-rs`' tests (such as
  `make`) are outside the scope of this document.
  ## Unaudited Required Dependencies
  