Merge pull request #8298 from ahocevar/ol-readme

Add README for ol package

src/ol/README.md

@@ -0,0 +1,52 @@
+# ol
+
+OpenLayers as ES modules.
+
+## Usage
+
+Add the `ol` package as a dependency to your project.
+
+    npm install ol --save
+
+Import just what you need for your application:
+
+```js
+import Map from 'ol/Map';
+import View from 'ol/View';
+import TileLayer from 'ol/layer/Tile';
+import XYZ from 'ol/source/XYZ';
+
+new Map({
+  target: 'map',
+  layers: [
+    new TileLayer({
+      source: new XYZ({
+        url: 'https://{a-c}.tile.openstreetmap.org/{z}/{x}/{y}.png'
+      })
+    })
+  ],
+  view: new View({
+    center: [0, 0],
+    zoom: 2
+  })
+});
+```
+
+See the following examples for more detail on bundling OpenLayers with your application:
+
+ * Using [Rollup & Uglify](https://gist.github.com/tschaub/8beb328ea72b36446fc2198d008287de)
+ * Using [Rollup & Closure Compiler](https://gist.github.com/tschaub/32a5692bedac5254da24fa3b12072f35)
+ * Using [Webpack & Uglify](https://gist.github.com/tschaub/79025aef325cd2837364400a105405b8)
+ * Using [Webpack & Closure Compiler](https://gist.github.com/ahocevar/8ceafc6293455ba491dd9be12c15761f)
+ * Using [Browserify & Uglify](https://gist.github.com/tschaub/4bfb209a8f809823f1495b2e4436018e)
+
+## Module Identifiers
+
+The module identifiers shown in the above snippet (e.g. `ol/Map`, note the CamelCase module name) are default exports of constructors. There are also modules like 'ol/proj' (note the lowercase module name), which provide named exports for utility functions and constants, e.g.
+
+```js
+import {fromLonLat} from 'ol/proj';
+
+map.setCenter(fromLonLat([16, 48]));
+```
+See the [API documentation](http://openlayers.org/en/latest/apidoc/) for a reference of all modules, and just keep in mind: CamelCase modules provide a default export, lowercase modules provide named exports.