Error in maximum price calculation 

When calculating the auction sore, `sp_hi` and `sp_hmax` are calculated as the maximum of projects in that auction round and not prescribed externally, as they should. [See here](https://github.com/JakobBD/cacoca/blob/d1432207590f5b223eb309a77ebfcedc38139f1c/cacoca/calc/calc_auction_quantities.py#L99-L104)