Switch to GitHub actions, remove Travis

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.github/workflows/build.yml

@@ -0,0 +1,11 @@
+on: [push, pull_request]
+name: build
+jobs:
+  lint:
+    runs-on: ubuntu-latest
+    steps:
+      - uses: actions/checkout@master
+      - name: lint
+        uses: Roang-zero1/factorio-mod-luacheck@master
+        with:
+          luacheckrc_url: ""

.travis.yml

@@ -1,15 +0,0 @@
-dist: bionic
-language: python
-
-python:
-  - 3.7.1
-
-install:
-  - sudo apt-get update -qq
-  - sudo apt-get install -qqq luarocks
-  - pip3 install pre-commit
-  - luarocks install --local luacheck
-
-script:
-  - pre-commit run --all-files
-  - $HOME/.luarocks/bin/luacheck .