Migrate GitHub Actions

.github/workflows/push.yml

@@ -0,0 +1,39 @@
+on: push
+name: main workflow
+jobs:
+  lint:
+    runs-on: ubuntu-latest
+    steps:
+    - uses: actions/checkout@master
+    - name: lint
+      uses: docker://golangci/golangci-lint:latest
+      with:
+        entrypoint: golangci-lint
+        args: run --disable-all --enable=gofmt --enable=vet --enable=gocyclo --enable=golint
+          --enable=ineffassign --enable=misspell --deadline=5m
+    - name: tidy
+      uses: docker://golang:1.12
+      env:
+        GOPATH: /github/workspace/.go
+      with:
+        entrypoint: go
+        args: mod tidy
+    - name: download
+      uses: docker://golang:1.12
+      env:
+        GOPATH: /github/workspace/.go
+      with:
+        entrypoint: go
+        args: mod download
+    - name: check modified
+      uses: docker://alpine/git:latest
+      with:
+        entrypoint: sh
+        args: -c "! git status | grep modified"
+    - name: test
+      uses: docker://golang:1.12
+      env:
+        GOPATH: /github/workspace/.go
+      with:
+        entrypoint: go
+        args: test ./...