SPRINGFIELD — The state’s Republican governor began a controversial special legislative session today with an uncontroversial step: prohibiting certain pay increases for legislators.Gov. Bruce Rauner this morning signed House Bill 634, which prohibits cost-of-living adjustments for legislators this fiscal year and keeps constant their mileage and per diem payments for such overtime sessions.The going rate for lodging and meals is enshrined in law at $111 per day, and reimbursement for automobile travel is 39 …