Clarify introduction to "Ranges"

Changed some of the language and syntax used in the introduction of the "Ranges" section for more accuracy and clarity.

Author: FrogBomb

src/main/scala/stdlib/Ranges.scala

@@ -12,9 +12,11 @@ import org.scalatest._
  */
 object Ranges extends FlatSpec with Matchers with org.scalaexercises.definitions.Section {
 
-  /** A Range is an ordered sequence of integers that are equally spaced apart. For example, "1, 2, 3" is a range, as is "5, 8, 11, 14". To create a range in Scala, use the predefined methods `to` and `by`. `1 to 3` generates `Range(1, 2, 3)` and `5 to 14 by 3` generates `Range(5, 8, 11, 14)`.
+  /** A Range is an ordered sequence of integers that are equally spaced apart. For example, "1, 2, 3" is a range, as is "5, 8, 11, 14". To create a range in Scala, use the predefined methods `to`, `until`, and `by`. `1 to 3` generates "1, 2, 3" and `5 to 14 by 3` generates "5, 8, 11, 14".
    *
-   * If you want to create a range that is exclusive of its upper limit, then use the convenience method `until` instead of `to`: `1 until 3` generates `Range(1, 2)`.
+   * If you want to create a range that is exclusive of its upper limit, then use `until` instead of `to`: `1 until 3` generates "1, 2".
+   * 
+   * Note that `Range(a, b, c)` is the same as `a until b by c`
    *
    * Ranges are represented in constant space, because they can be defined by just three numbers: their start, their end, and the stepping value. Because of this representation, most operations on ranges are extremely fast.
 	*