Add CodeQL analysis

Author: flashcode

.github/workflows/codeql-analysis.yml

@@ -0,0 +1,36 @@
+name: "CodeQL"
+
+on:
+  push:
+    branches: [ master ]
+  pull_request:
+    branches: [ master ]
+
+jobs:
+  analyze:
+    name: Analyze
+    runs-on: ubuntu-latest
+    permissions:
+      actions: read
+      contents: read
+      security-events: write
+
+    strategy:
+      fail-fast: false
+      matrix:
+        language: [ 'python' ]
+
+    steps:
+    - name: Checkout repository
+      uses: actions/checkout@v2
+
+    - name: Initialize CodeQL
+      uses: github/codeql-action/init@v1
+      with:
+        languages: ${{ matrix.language }}
+
+    - name: Autobuild
+      uses: github/codeql-action/autobuild@v1
+
+    - name: Perform CodeQL Analysis
+      uses: github/codeql-action/analyze@v1

README.md

@@ -2,6 +2,7 @@
 
 [![PyPI](https://img.shields.io/pypi/v/msgcheck.svg)](https://pypi.org/project/msgcheck/)
 [![Build Status](https://github.com/flashcode/msgcheck/workflows/CI/badge.svg)](https://github.com/flashcode/msgcheck/actions?query=workflow%3A%22CI%22)
+[![Build Status](https://github.com/flashcode/msgcheck/workflows/CodeQL/badge.svg)](https://github.com/flashcode/msgcheck/actions?query=workflow%3A%22CodeQL%22)
 
 Msgcheck performs various checks on gettext files (with extension `.po`):