The proposed $20.5 million purchase by the city of Denver of the Park Hill Golf Club in northeast Denver from the nonprofit Clayton Early Learning organization is on hold, according to reports. The Denver Post and KMGH-Channel 7 both report that the sale -- proposed in September -- is been held up because of issues between the owner and Arcis Golf, the Dallas-based company that leases and operates the course. Reportedly, Arcis -- whose lease expires at the end of 2018 -- has recently signaled that…