Add range generator for floating points

lib/make/numbers.js

@@ -34,6 +34,14 @@ make.number = {
   range: function () {
     return random.pick([1, 2, 3, 4, 6, 8, 16, 32, 64, make.number.tiny])
   },
+  frange: function (min, max, precision) {
+    let x = Math.random() * (min - max) + max
+    if (precision) {
+      let power = Math.pow(10, precision || 0)
+      x = Math.round(x * power) / power
+    }
+    return x
+  },
   tiny: function () {
     return Math.pow(2, random.number(12))
   },