Perficient Inc., the St. Louis-based IT services provider, has closed on its $35.7 million acquisition of Zeon Solutions Inc. of Milwaukee. The company also expanded its existing credit facility, which provides for borrowing of up to $125 million, $35 million more than what was previously available, Perficient officials said Friday. Wells Fargo Bank is also now a lender to Perficient under the facility. "The expansion of our credit facility ensures we'll continue to have the financial flexibility…