Better test printing (#9)

* Better test printing

The current test results are confusing as they are written as rationals.
Let's write them as float strings.

* Update round_test.go

lets print both args the same to make it even easier

Co-authored-by: Wade Simmons <[email protected]>

Author: Karel Bilek

round_test.go

@@ -184,7 +184,7 @@ func testRounding(t *testing.T, a, b string, prec int, method RoundingMode) {
 	Round(x, prec, method)
 
 	if x.Cmp(y) != 0 {
-		t.Errorf("test Round(%v, %v, %v) == %s. Got %v", a, prec, method, y, x)
+		t.Errorf("test Round(%v, %v, %v) == %s. Got %v", a, prec, method, y.FloatString(3), x.FloatString(3))
 	}
 }