To avoid scalpers' price, the bot now understand filters on prices
using a minimum and maximum value, in a currency and a pattern to
detect the model.
Example:
```
"price_ranges": [
{"model": "3090", "max": 3000, "currency": "EUR"},
{"model": "3080", "max": 1600, "currency": "EUR"},
{"model": "3070", "max": 1200, "currency": "EUR"}
],
```
More details in README.md.
Signed-off-by: Julien Riou <julien@riou.xyz>
