SACRAMENTO - Every property owner in California, no matter how big or small or valuable the parcel, faces paying a flat $50 tax to fund schools under a measure voters will be asked to approve in November. Although it's still early in the election season, the move already is generating criticism from taxpayer groups and property owners who say it's a regressive tax and adds to the burden on average citizens who are already overtaxed. Proponents of Proposition 88 - authored by EdVoice, a coalition that includes backing from such wealthy philanthropists as Netflix CEO Reed Hastings, Silicon Valley investor...