Http 500 errors (#255)
Http 500 errors (#255)

* Handle all 5xx HTTP errors
BitBotFactory/poloniexlendingbot,BitBotFactory/poloniexlendingbot,laxdog/poloniexlendingbot,Mikadily/poloniexlendingbot,Mikadily/poloniexlendingbot,mahiso/poloniexlendingbot,Mikadily/poloniexlendingbot,laxdog/poloniexlendingbot,mahiso/poloniexlendingbot,BitBotFactory/poloniexlendingbot,laxdog/poloniexlendingbot,mahiso/poloniexlendingbot,mahiso/poloniexlendingbot,BitBotFactory/poloniexlendingbot