Add waypoints parameter to viaroute API (#5345)

* Add silent waypoints to viaroute API.

docs/nodejs/api.md

@@ -57,6 +57,7 @@ Returns the fastest route between two or more coordinates while visiting the way
     -   `options.overview` **[String](https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/String)** Add overview geometry either `full`, `simplified` according to highest zoom level it could be display on, or not at all (`false`). (optional, default `simplified`)
     -   `options.continue_straight` **[Boolean](https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Boolean)?** Forces the route to keep going straight at waypoints and don't do a uturn even if it would be faster. Default value depends on the profile.
     -   `options.approaches` **[Array](https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Array)?** Keep waypoints on curb side. Can be `null` (unrestricted, default) or `curb`.
+    -   `options.waypoints` **[Array](https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Array)?** Indices to coordinates to treat as waypoints.  If not supplied, all coordinates are waypoints.  Must include first and last coordinate index.
                          `null`/`true`/`false`
 -   `callback` **[Function](https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Statements/function)**
 
@@ -210,6 +211,7 @@ if they can not be matched successfully.
     -   `options.radiuses` **[Array](https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Array)?** Standard deviation of GPS precision used for map matching. If applicable use GPS accuracy. Can be `null` for default value `5` meters or `double >= 0`.
     -   `options.gaps` **[String](https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/String)?** Allows the input track splitting based on huge timestamp gaps between points. Either `split` or `ignore` (optional, default `split`).
     -   `options.tidy` **[Boolean](https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Boolean)?** Allows the input track modification to obtain better matching quality for noisy tracks (optional, default `false`).
+    -   `options.waypoints` **[Array](https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Array)?** Indices to coordinates to treat as waypoints.  If not supplied, all coordinates are waypoints.  Must include first and last coordinate index.
 -   `callback` **[Function](https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Statements/function)**
 
 **Examples**