variantly 0.4.0

Derive helper methods for enum variants that are familiar from `std::option::Option` & `std::result::Result` such as `unwrap_or` or `and_then`.
Documentation
name: Rust

on:
  push:
    branches: [ main, develop ]
  pull_request:
    branches: [ main, develop ]

env:
  CARGO_TERM_COLOR: always

jobs:
  build:

    runs-on: ubuntu-latest

    steps:
    - uses: actions/checkout@v2
    - name: Build
      run: cargo build --verbose
    - name: Run tests
      run: cargo test --verbose