Label value not decoded

[wa0x6e]

When pushing metrics, most libraries do encode the labels value before sending them, following the specs by the pushgateway (https://github.com/prometheus/pushgateway/blob/master/README.md#url)

So sending metrics{instance="localhost:80"} 1 should return metrics{instance="localhost:80"} 1 on the gateway side.

The issue I have with gravel-gateway is that the labels value are not being decoded, and the gateway display instead:

metrics{instance="localhost%3A80"} 1

Fix will be to decode all labels value before any processing