Youbike returns negative values for "free_bikes"

[futuretap]

empty_slots is negative sometimes, too. https://api.citybik.es/v2/networks/youbike-putian-city

[eskerda]

that's what the canonical source is reporting. System seems offline atm.

https://putian.ptyoubike.com/station/map

we could clamp the numbers to 0. Not sure what to make out of it or if the value on itself has any significant value