Replace Travis with GHA (#296)

Author: christopher-dG

.github/workflows/CI.yml

@@ -0,0 +1,38 @@
+name: CI
+on:
+  pull_request:
+    branches:
+      - master
+  push:
+    branches:
+      - master
+jobs:
+  test:
+    runs-on: ubuntu-latest
+    strategy:
+      matrix:
+        group:
+          - Interface
+    steps:
+      - uses: actions/checkout@v2
+      - uses: julia-actions/setup-julia@v1
+        with:
+          version: 1
+      - uses: actions/cache@v1
+        env:
+          cache-name: cache-artifacts
+        with:
+          path: ~/.julia/artifacts
+          key: ${{ runner.os }}-test-${{ env.cache-name }}-${{ hashFiles('**/Project.toml') }}
+          restore-keys: |
+            ${{ runner.os }}-test-${{ env.cache-name }}-
+            ${{ runner.os }}-test-
+            ${{ runner.os }}-
+      - uses: julia-actions/julia-buildpkg@v1
+      - uses: julia-actions/julia-runtest@v1
+        env:
+          GROUP: ${{ matrix.group }}
+      - uses: julia-actions/julia-processcoverage@v1
+      - uses: codecov/codecov-action@v1
+        with:
+          file: lcov.info

.travis.yml

@@ -1,7 +1,6 @@
 # DiffEqOperators.jl
 
-[![Build Status](https://travis-ci.org/SciML/DiffEqOperators.jl.svg?branch=master)](https://travis-ci.org/SciML/DiffEqOperators.jl)
-[![Build status](https://ci.appveyor.com/api/projects/status/au9knv63u9oh1aie?svg=true)](https://ci.appveyor.com/project/ChrisRackauckas/diffeqoperators-jl)
+[![Build Status](https://github.com/SciML/DiffEqOperators.jl/workflows/CI/badge.svg)](https://github.com/SciML/DiffEqOperators.jl/actions?query=workflow%3ACI)
 [![GitlabCI](https://gitlab.com/JuliaGPU/DiffEqOperators.jl/badges/master/pipeline.svg)](https://gitlab.com/JuliaGPU/DiffEqOperators.jl/pipelines)
 [![Stable](https://img.shields.io/badge/docs-stable-blue.svg)](http://diffeqoperators.sciml.ai/stable/)
 [![Dev](https://img.shields.io/badge/docs-dev-blue.svg)](http://diffeqoperators.sciml.ai/dev/)