use +nightly (#2)

* use +nightly

.github/workflows/rust.yml

@@ -0,0 +1,40 @@
+name: Rust
+
+on:
+  push:
+    branches: [ master ]
+  pull_request:
+    branches: [ master ]
+
+env:
+  CARGO_TERM_COLOR: always
+
+jobs:
+  build:
+
+    runs-on: ubuntu-latest
+
+    steps:
+    - uses: actions/checkout@v2
+    - name: Install latest nightly
+      uses: actions-rs/toolchain@v1
+      with:
+          toolchain: nightly
+          override: true
+          components: rustfmt, clippy
+
+    # `cargo check` command here will use installed `nightly`
+    # as it is set as an "override" for current directory
+
+    - name: Run cargo check
+      uses: actions-rs/cargo@v1
+      with:
+        command: check
+    - name: Run cargo Build
+      uses: actions-rs/cargo@v1
+      with:
+        command: build
+    - name: Run cargo test
+      uses: actions-rs/cargo@v1
+      with:
+        command: test