add github actions

.github/workflows/CI.yml

@@ -0,0 +1,47 @@
+name: CI
+
+# Controls when the action will run. 
+on: 
+  push:
+  pull_request:
+  workflow_dispatch:
+  release:
+    types: [published]
+
+# A workflow run is made up of one or more jobs that can run sequentially or in parallel
+jobs:
+  build:
+    name: build
+    runs-on: ubuntu-20.04
+    if: ${{ !(github.event_name == 'push' && startsWith(github.ref, 'refs/tags/')) }}
+    steps:
+      - uses: actions/checkout@v2
+      - name: Start build
+        run: |
+          make all ARCH=mips24kec BUILD_STATIC=y && mv trojan trojan-mips24kec-static
+          make clean
+          make all ARCH=mips1004kec BUILD_STATIC=y && mv trojan trojan-mips1004kec-static
+          make clean
+          make all ARCH=aarch64 BUILD_STATIC=y && mv trojan trojan-aarch64-static
+          make clean
+          make all ARCH=armhf BUILD_STATIC=y && mv trojan trojan-armhf-static
+      - name: Create archive
+        if: ${{ github.event_name != 'release' && success() }}
+        run: |
+          ls -lh trojan-*
+          tar -cvJf trojan-static.tar.xz trojan-*
+      - name: Upload images to Artifact
+        if: ${{ github.event_name != 'release' && success() }}
+        uses: actions/upload-artifact@v2.2.1
+        with:
+          name: trojan-static
+          path: trojan-static.tar.xz
+      - name: Upload images to Releases
+        if: ${{ github.event_name == 'release' && success() }}
+        uses: svenstaro/upload-release-action@2.2.0
+        with:
+          repo_token: ${{ secrets.GITHUB_TOKEN }}
+          file: trojan-*
+          tag: ${{ github.ref }}
+          overwrite: true
+          file_glob: true