Fuzzing workflow (#230)

Add a CIFuzz workflow (and a corresponding badge to the README)

.github/workflows/fuzz.yml

@@ -0,0 +1,23 @@
+name: CIFuzz
+on: [pull_request]
+jobs:
+  Fuzzing:
+    runs-on: ubuntu-latest
+    steps:
+    - name: Build Fuzzers
+      uses: google/oss-fuzz/infra/cifuzz/actions/build_fuzzers@master
+      with:
+        oss-fuzz-project-name: 'mdbtools'
+        dry-run: false
+    - name: Run Fuzzers
+      uses: google/oss-fuzz/infra/cifuzz/actions/run_fuzzers@master
+      with:
+        oss-fuzz-project-name: 'mdbtools'
+        fuzz-seconds: 600
+        dry-run: false
+    - name: Upload Crash
+      uses: actions/upload-artifact@v1
+      if: failure()
+      with:
+        name: artifacts
+        path: ./out/artifacts

README.md

@@ -1,5 +1,6 @@
 [![Build Status](https://github.com/mdbtools/mdbtools/workflows/build/badge.svg)](https://github.com/mdbtools/mdbtools/actions)
 [![Build status](https://ci.appveyor.com/api/projects/status/22wwy5d0rrmk6e3c/branch/dev?svg=true)](https://ci.appveyor.com/project/evanmiller/mdbtools/branch/dev)
+[![Fuzzing Status](https://oss-fuzz-build-logs.storage.googleapis.com/badges/mdbtools.svg)](https://bugs.chromium.org/p/oss-fuzz/issues/list?sort=-opened&can=1&q=proj:mdbtools)
 
 Welcome to the exciting world of MDB Tools! MDB Tools is a set of programs to
 help you extract data from Microsoft Access files in various settings. See the