SPRINGFIELD — It’s crunch time for constitutional amendments.State lawmakers must pass any proposed constitutional changes through both the House and Senate by early next week to permit voters to have their say in November’s general election.And a few of the ideas still percolating at the Statehouse today included a change from a flat tax to a graduated income tax, a revamped redistricting plan, a measure that would protect a special state transportation fund and a new idea to eliminate the lieutenant …