reads in World bank irrigation data: WBirrigation data .csv file as magclass object from Jones, William I. 1995. "World Bank and Irrigation." Washington, D.C.: World Bank. Bonsch et al. (2015) "Environmental Flow Provision: Implications for Agricultural Water and Land-Use at the Global Scale": Table A1 - Investment costs for expanding irrigation infrastructure in US$ per hectare. Based on: World Bank Irrigation Investment Cost Data. William I. Jones(1991) "The World Bank and Irrigation" (World Bank Operations Evaluation Study)