message: Fix description of `ff`.
diff: name = "ff"
  version = "0.1.0"
  authors = ["Sean Bowe <ewillbefull@gmail.com>"]
  -description = "Procedural macro library used to build custom prime field implementations"
  +description = "Library for building and interfacing with finite fields"
  documentation = "https://github.com/ebfull/ff"
  homepage = "https://github.com/ebfull/ff"
  license = "MIT/Apache-2.0"
  