Add non regress test for #32

tests/sat/mult.smt2

+;; produced by colibri.drv ;;
+(set-logic ALL)
+(set-info :smt-lib-version 2.6)
+
+(define-fun in_range1 ((x Int)) Bool (and (<= (- 2147483648) x)
+                                     (<= x 2147483647)))
+
+(declare-const b11 Int)
+(assert (in_range1 b11))
+
+(assert (not (<= (* b11 b11) 2147483647)))
+(check-sat)