Replace Travis with GHA (#223)

.github/workflows/ci.yaml

@@ -0,0 +1,56 @@
+name: CI
+on:
+  push:
+    branches:
+      - staging
+      - trying
+      - master
+
+jobs:
+
+  tests:
+    name: Tests
+    runs-on: ubuntu-latest
+
+    strategy:
+      matrix:
+        rust: [stable, nightly]
+
+    steps:
+      - uses: actions/checkout@v2
+      - uses: actions-rs/toolchain@v1
+        with:
+          toolchain: ${{ matrix.rust }}
+          profile: minimal
+          override: true
+      - run: cargo test
+      - run: cargo test --all-features
+
+  clippy:
+    name: "Clippy: stable"
+    runs-on: ubuntu-latest
+    continue-on-error: true
+    steps:
+      - uses: actions/checkout@v2
+      - uses: actions-rs/toolchain@v1
+        with:
+          toolchain: stable
+          profile: minimal
+          components: clippy
+          override: true
+      - uses: actions-rs/clippy-check@v1
+        with:
+          token: ${{ github.token }}
+
+  rustfmt:
+    name: "Format: stable"
+    runs-on: ubuntu-latest
+    steps:
+      - uses: actions/checkout@v2
+      - uses: actions-rs/toolchain@v1
+        with:
+          toolchain: stable
+          profile: minimal
+          components: rustfmt
+          override: true
+      - run: cargo fmt -- --check

bors.toml

@@ -1,5 +1,6 @@
 status = [
-  "continuous-integration/travis-ci/push",
+  "Tests",
+  "Format: stable",
 ]
 
 block_labels = [