Elastic Tile Service support for 10 zoom

ETS does not support 10 zoom at the time of this commit, but it will by
the time of the release.

docs/kibana-yml.asciidoc

@@ -17,7 +17,7 @@ dashboards. Kibana creates a new index if the index doesn’t already exist.
 [[tilemap-settings]]`tilemap.url:`:: *Default: `"https://tiles.elastic.co/v1/default/{z}/{x}/{y}.png?elastic_tile_service_tos=agree&my_app_name=kibana"`* The URL to the tile
 service that Kibana uses to display map tiles in tilemap visualizations.
 `tilemap.options.minZoom:`:: *Default: 1* The minimum zoom level.
-`tilemap.options.maxZoom:`:: *Default: 7* The maximum zoom level.
+`tilemap.options.maxZoom:`:: *Default: 9* The maximum zoom level.
 `tilemap.options.attribution:`:: *Default: `"© [Elastic Tile Service](https://www.elastic.co/elastic-tile-service)"`* The map attribution string.
 `tilemap.options.subdomains:`:: An array of subdomains used by the tile service.
 Specify the position of the subdomain the URL with the token `{s}`.

src/core_plugins/tests_bundle/tests_entry_template.js

@@ -32,7 +32,7 @@ window.__KBN__ = {
       url: 'https://tiles.elastic.co/v1/default/{z}/{x}/{y}.png?my_app_name=kibana&my_app_version=1.2.3&elastic_tile_service_tos=agree',
       options: {
         minZoom: 1,
-        maxZoom: 7,
+        maxZoom: 9,
         attribution: '© [Elastic Tile Service](https://www.elastic.co/elastic_tile_service)'
       }
     }

src/server/config/schema.js

@@ -139,7 +139,7 @@ module.exports = () => Joi.object({
     options: Joi.object({
       attribution: Joi.string().default('© [Elastic Tile Service](https://www.elastic.co/elastic-tile-service)'),
       minZoom: Joi.number().min(1, 'Must not be less than 1').default(1),
-      maxZoom: Joi.number().default(7),
+      maxZoom: Joi.number().default(9),
       tileSize: Joi.number(),
       subdomains: Joi.array().items(Joi.string()).single(),
       errorTileUrl: Joi.string().uri(),