Revert "Revert "Import external/python/jinja into master""

This reverts commit 81aec74062b5c629b3408f7f3d18343ec0bbcab8.

Reason for revert: It seems Jinja folder is empty. Revert the revert to add files back.

Third-party review: ag/11821018
Change-Id: I4429a3b3448cdf2eb62ec388392a2a29fa3dbc21

2 files changed, 85 insertions, 0 deletions

diff --git a/.github/ISSUE_TEMPLATE.md b/.github/ISSUE_TEMPLATE.md
new file mode 100644
index 00000000..4273496d
--- /dev/null
+++ b/.github/ISSUE_TEMPLATE.md
@@ -0,0 +1,33 @@
+The issue tracker is a tool to address bugs in Jinja itself.
+Please use the #pocoo IRC channel on freenode or Stack Overflow for general
+questions about using Jinja or issues not related to Jinja.
+
+If you'd like to report a bug in Jinja, fill out the template below and provide
+any extra information that may be useful / related to your problem.
+Ideally, you create an [MCVE](http://stackoverflow.com/help/mcve) reproducing
+the problem before opening an issue to ensure it's not caused by something in
+your code.
+
+---
+
+## Expected Behavior
+Tell us what should happen
+
+## Actual Behavior
+Tell us what happens instead
+
+## Template Code
+```jinja
+Paste the template code (ideally a minimal example) that causes the issue
+
+```
+
+## Full Traceback
+```pytb
+Paste the full traceback in case there is an exception
+
+```
+
+## Your Environment
+* Python version:
+* Jinja version:
diff --git a/.github/workflows/tests.yaml b/.github/workflows/tests.yaml
new file mode 100644
index 00000000..a826fda6
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+++ b/.github/workflows/tests.yaml
@@ -0,0 +1,52 @@
+name: Tests
+on:
+  push:
+    branches:
+      - master
+      - '*.x'
+  pull_request:
+    branches:
+      - master
+      - '*.x'
+jobs:
+  tests:
+    name: ${{ matrix.name }}
+    runs-on: ${{ matrix.os }}
+    strategy:
+      fail-fast: false
+      matrix:
+        include:
+          - {name: Linux, python: '3.8', os: ubuntu-latest, tox: py38}
+          - {name: '3.7', python: '3.7', os: ubuntu-latest, tox: py37}
+          - {name: '3.6', python: '3.6', os: ubuntu-latest, tox: py36}
+          - {name: 'PyPy', python: pypy3, os: ubuntu-latest, tox: pypy3}
+          - {name: Style, python: '3.8', os: ubuntu-latest, tox: style}
+          - {name: Docs, python: '3.8', os: ubuntu-latest, tox: docs}
+          - {name: Windows, python: '3.8', os: windows-latest, tox: py38}
+          - {name: Mac, python: '3.8', os: macos-latest, tox: py38}
+    steps:
+      - uses: actions/checkout@v2
+      - uses: actions/setup-python@v2
+        with:
+          python-version: ${{ matrix.python }}
+      - name: update pip
+        run: |
+          pip install -U wheel
+          pip install -U setuptools
+          python -m pip install -U pip
+      - name: get pip cache dir
+        id: pip-cache
+        run: echo "::set-output name=dir::$(pip cache dir)"
+      - name: cache pip
+        uses: actions/cache@v1
+        with:
+          path: ${{ steps.pip-cache.outputs.dir }}
+          key: pip|${{ runner.os }}|${{ matrix.python }}|${{ hashFiles('setup.py') }}|${{ hashFiles('requirements/*.txt') }}
+      - name: cache pre-commit
+        uses: actions/cache@v1
+        with:
+          path: ~/.cache/pre-commit
+          key: pre-commit|${{ matrix.python }}|${{ hashFiles('.pre-commit-config.yaml') }}
+        if: matrix.tox == 'style'
+      - run: pip install tox
+      - run: tox -e ${{ matrix.tox }}