Switch CI to GH Actions.

.github/workflows/TagBot.yml

@@ -0,0 +1,15 @@
+name: TagBot
+on:
+  issue_comment:
+    types:
+      - created
+  workflow_dispatch:
+jobs:
+  TagBot:
+    if: github.event_name == 'workflow_dispatch' || github.actor == 'JuliaTagBot'
+    runs-on: ubuntu-latest
+    steps:
+      - uses: JuliaRegistries/TagBot@v1
+        with:
+          token: ${{ secrets.GITHUB_TOKEN }}
+          ssh: ${{ secrets.DOCUMENTER_KEY }}

.github/workflows/ci.yml

@@ -0,0 +1,44 @@
+name: CI
+
+on:
+  push:
+    branches:
+      - 'master'
+      - 'release-'
+    tags: '*'
+  pull_request:
+
+jobs:
+  test:
+    name: Julia ${{ matrix.version }} - ${{ matrix.os }} - ${{ github.event_name }}
+    runs-on: ${{ matrix.os }}
+    strategy:
+      matrix:
+        version:
+          - '1.0'
+          - '1'
+          - 'nightly'
+        os:
+          - ubuntu-latest
+          - macos-latest
+          # - windows-latest
+    steps:
+      - uses: actions/checkout@v2
+      - uses: julia-actions/setup-julia@v1
+        with:
+          version: ${{ matrix.version }}
+      - name: "Pkg.instantiate and install cli"
+        run: |
+          echo "${PWD}/bin" >> $GITHUB_PATH
+          julia --project -e 'using Pkg; Pkg.instantiate()'
+          julia --project -e 'using jlpkg; jlpkg.install(; command = "jlpkg-ci", destdir = joinpath(pwd(), "bin"))'
+      - name: "Run tests (Unix)"
+        if: matrix.os == 'ubuntu-latest' || matrix.os == 'macOS-latest'
+        run: jlpkg-ci --project test --coverage
+      - name: "Run tests (Windows)"
+        if: matrix.os == 'windows-latest'
+        run: cmd /c jlpkg-ci --project test --coverage
+      - uses: julia-actions/julia-processcoverage@v1
+      - uses: codecov/codecov-action@v1
+        with:
+          file: lcov.info