rfc-4226 0.2.0

Implementation of IETF RFC 4226 (HOTP).
Documentation
language: rust
rust:
  - stable
  - beta
  - nightly
before_script:
- rustup component add rustfmt clippy
script:
- cargo fmt --all -- --check
- cargo build --verbose
- cargo test --all --verbose
matrix:
  allow_failures:
    - rust: nightly
  fast_finish: true
  cache: cargo