SACRAMENTO - California has put a lot of expenses on plastic lately and may add billions more next year. In March 2004, voters approved $27 billion worth of borrowing, including a $15 billion bond to refinance state debt. Last fall, they passed a $3 billion bond to pay for research into stem-cell technology, along with $750 million for seismic improvements at children's hospitals. Since then, legislation to place almost $30 billion in new borrowing on next year's fall ballot has passed initial committee tests. The bonds -- which could pay for projects ranging from a new courthouse in downtown San...