Updated README files, .gitignore and .env.example

api/.env.example

@@ -0,0 +1,9 @@
+# MYSQL Database
+MYSQL_HOST=
+MYSQL_PORT=
+MYSQL_DATABASE=
+MYSQL_USER=
+MYSQL_PASSWORD=
+
+# Flask secret key
+SECRET_KEY=

api/README.md

@@ -0,0 +1,41 @@
+# API
+
+Aktienbot API
+
+## Development
+1. Create virtual environment `python -m venv venv env/Scripts/activate`
+2. Install requirements `pip install -r api/requirements.txt`
+3. Set environment variables (see list below)
+   1. Use `.env`-file in `api` directory like `.env.example`
+   2. Or set variables using `export` or `set` commands. (Windows `set`, Linux `export`)
+4. Run api `python api/app.py`      
+
+## Environment variables
+```
+    # Flask secret key
+    SECRET_KEY=
+    
+    # MYSQL Connection
+    MYSQL_USER=
+    MYSQL_PASSWORD=
+    MYSQL_HOST=
+    MYSQL_PORT=
+    MYSQL_DATABASE=
+```
+
+## Docker
+```
+docker run -d \
+    --name aktienbot_api \
+    --hostname aktienbot_api \
+    --publish 80:80 \
+    --env "SECRET_KEY=" \
+    --env "MYSQL_USER=" \
+    --env "MYSQL_PASSWORD=" \
+    --env "MYSQL_HOST=" \
+    --env "MYSQL_PORT=" \
+    --env "MYSQL_DATABASE=" \
+    --restart unless-stopped \
+    registry.flokaiser.com/aktienbot/api:latest
+```
+or load environment variables from file by using `--env-file <filename>`