Add Github Actions CI

Author: shesek

.github/workflows/rust.yml

@@ -0,0 +1,42 @@
+name: CI
+
+on: [push, pull_request]
+
+jobs:
+  test:
+    runs-on: ubuntu-18.04
+    env:
+      CARGO_TERM_COLOR: always
+
+    steps:
+    - uses: actions/checkout@v2
+
+    - name: Cache cargo registry
+      uses: actions/cache@v1
+      with:
+        path: ~/.cargo/registry
+        key: ${{ runner.os }}-cargo-registry-${{ hashFiles('**/Cargo.lock') }}
+
+    - name: Cache cargo index
+      uses: actions/cache@v1
+      with:
+        path: ~/.cargo/git
+        key: ${{ runner.os }}-cargo-index-${{ hashFiles('**/Cargo.lock') }}
+
+    - name: Cache cargo build
+      uses: actions/cache@v1
+      with:
+        path: target
+        key: ${{ runner.os }}-cargo-build-target-${{ hashFiles('**/Cargo.lock') }}
+
+    #- name: Check formatting
+    #  run: cargo fmt -- --check
+
+    - name: Check for errors
+      run: cargo check
+
+    - name: Run tests (Bitcoin mode)
+      run: cargo test
+
+    - name: Run tests (Liquid mode)
+      run: cargo test --features liquid