TALLAHASSEE, Fla. — The Florida legislature is considering a bill that would end permanent alimony in most future divorces, setting up formulas that would set time limits and amounts based on the length of the marriage and the income difference between the spouses. Sponsored by Rep. Colleen Burton and Sen. Kelli Stargel, both Polk County Republicans, the bill calls for payments that would last to between 25 and 75 percent of the length of the marriage. Judges could break the guidelines only in unusual cases …