add linter

.flake8

@@ -0,0 +1,11 @@
+[flake8]
+ignore = 
+    E302
+    E501
+exclude =
+    .git,
+    __pycache__,
+    docs/source/conf.py,
+    old,
+    build,
+    dist

.github/workflows/linter.yml

@@ -0,0 +1,29 @@
+name: PEP8
+
+on:
+  push:
+    branches:
+      - main
+  pull_request:
+
+jobs:
+  build:
+
+    runs-on: ubuntu-latest
+    strategy:
+      matrix:
+        python-version: [3.7, 3.9]
+
+    steps:
+    - uses: actions/checkout@v2
+    - name: Set up Python ${{ matrix.python-version }}
+      uses: actions/setup-python@v2
+      with:
+        python-version: ${{ matrix.python-version }}
+    - name: Install dependencies
+      run: |
+        python -m pip install --upgrade pip
+        pip install flake8
+    - name: Flake8 Fink GRB
+      run: |
+        flake8 ../Fink_GRB