add workflows

.github/workflows/ci.yml

@@ -0,0 +1,44 @@
+on: [push, pull_request]
+
+name: check everything
+env:
+  CARGO_INCREMENTAL: 0
+jobs:
+  cargo-check:
+    name: cargo-check
+    runs-on: ${{matrix.os}}-latest
+    strategy:
+      matrix:
+        os: [ubuntu, windows, macos]
+    steps:
+      - name: Checkout
+        uses: actions/checkout@v2
+
+      - name: Install Rust toolchain
+        uses: actions-rs/toolchain@v1
+        with:
+          profile: minimal
+          toolchain: stable
+          override: true
+
+      - name: Rust Cache
+        uses: Swatinem/rust-cache@v1
+
+      - name: Install dependencies # for glfw and rfd
+        if: ${{matrix.os == 'ubuntu'}}
+        run: sudo apt update && sudo apt install --no-install-recommends libglfw3-dev libgtk-3-dev
+
+      - name: Fmt
+        run: cargo fmt --check
+
+      - name: Check
+        run: cargo check --workspace
+
+      - name: Clippy
+        run: cargo clippy --workspace -- -D warnings
+
+      - name: Build
+        run: cargo build --workspace
+
+      - name: Audit
+        run: cargo audit