providers: Bring math provider back into service

Sprig is missing some float math functions

providers/math/math.go

@@ -19,27 +19,10 @@ func (this *Provider) Package () string {
 // FuncMap fulfills the step.FuncProvider interface.
 func (this *Provider) FuncMap () template.FuncMap {
 	return template.FuncMap {
-		"add":  funcAdd,
-		"sub":  funcSub,
-		"mul":  funcMul,
-		"div":  funcDiv,
-		"pow":  math.Pow,
-		"sqrt": math.Sqrt,
+		"modf": funcModf,
 	}
 }
 
-func funcAdd (a, b float64) float64 {
-	return a + b
-}
-
-func funcSub (a, b float64) float64 {
-	return a - b
-}
-
-func funcMul (a, b float64) float64 {
-	return a * b
-}
-
-func funcDiv (a, b float64) float64 {
-	return a / b
+func funcModf (a, b float64) float64 {
+	return math.Mod(a, b)
 }