doc:Added README

README.md

+<img src="./app/static/images/MaDiPHS_logo.png" style="width: 400px; padding-bottom: 30px;"/>
+
+# Mock weather data source
+
+This a weather data source with no live data. It returns data from 2021 from one virtual location. It can be used for testing the API.
+
+The weather data source returns weather data following the IPM Decisions weather data format.
+
+The parameters provided are [parameter_id in square brackets]:
+
+*    Mean air temperature at 2m (°C) [1002]
+*    Minimum air temperature at 2m (°C) [1003]
+*    Maximum air temperature at 2m (°C) [1004]
+*    Mean air temperature at -10cm (°C) [1112]
+*    Precipitation (mm) [2001]
+*    Mean relative humidity at 2m (%) [3002]
+*    Leaf wetness at 2m (minutes/h) [3101]
+*    Instantaneous wind speed at 2m (m/s) [4002]
+*    Mean wind speed at 2m (m/s) [4003]
+*    Solar radiation (W/sqm) [5001]
+
+The log interval is either hourly (default) or daily
+
+## Usage
+
+`/weather_data?latitude=[]&longitude=[]&parameters=[,,]&timeStart=[]&timeEnd=[]&interval=[]`
+
+*    latitude and longitude are mandatory parameters. Coordinate system: WGS84 (Decimal degrees). It does however not affect the data returned from this service
+*    parameters are optional Parameters list
+*    timeStart and timeEnd are optional. Format: YYYY-mm-dd, e.g. 2021-10-28. If omitted, data from Jan-Dec of 2021 will be returned
+*    interval is optional. The default value is 3600 (hourly values). To get daily values, set interval=86400.
+
+## Example
+
+`/weather_data?latitude=50.109&longitude=10.961&parameters=1002,2001`
+
+## Development
+### Run locally
+* The application is built using Flask. 
+* Running the application using a virtualenv is recommended
+
+```bash
+cd [app_folder]
+# If first time: Create a virtualenv
+python3 -m venv mwdsvenv
+# Activate the virtualenv
+source init_flask_dev
+# Install all dependencies
+pip install -r requirements.txt
+# Start the app
+cd app
+flask run
+```
+
+If all goes well, this is the approximate output:
+
+```bash
+* Debug mode: on
+WARNING: This is a development server. Do not use it in a production deployment. Use a production WSGI server instead.
+ * Running on http://127.0.0.1:5000
+Press CTRL+C to quit
+ * Restarting with stat
+ * Debugger is active!
+ * Debugger PIN: 135-752-566
+```
+
+The application should be active on `http://localhost:5000/`