Add documentation about localConfig.js

docs/developer-guide/configuration-files.md

@@ -3,4 +3,5 @@
 MapStore2 (and every application developed with MapStore2) allows customization through configuration.
 Several configuration files (at development and / or run time) are available to configure all the different aspects of an application.
 
- * [Maps configuration](maps-configuration)
+ * [Application Configuration](local-config)
+ * [Maps configuration](maps-configuration)

docs/developer-guide/local-config.md

@@ -0,0 +1,58 @@
+# Application configuration
+The application will load by default it will load the `localConfig.js`
+
+You can load a custom configuration by passing the `localConfig` argument in query string:
+
+```
+localhost:8081/?localConfig=myConfig#/viewer/openlayers/0
+```
+
+
+The **localConfig** file contains the main information about URLs to load and plugins to load in the various modes.
+
+This is the main structure:
+```
+{
+  // URL of geoStore
+  "geoStoreUrl": "rest/geostore/",
+  // printURL the url of the print service, if any
+  "printUrl": "/geoserver-test/pdf/info.json",
+  // a string or an object for the proxy URL.
+  "proxyUrl": {
+    // if it is an object, the url entry holds the url to the proxy
+    "url": "/MapStore2/proxy/?url=",
+    // useCORS array contains a list of services that support CORS and so do not need a proxy
+    "useCORS": ["http://nominatim.openstreetmap.org", "https://nominatim.openstreetmap.org"]
+  },
+  // API keys for bing and mapquest services
+  "bingApiKey"
+  "mapquestApiKey"
+  // path to the translation files directory (if different from default)
+  "translationsPath"
+  // if true, every ajax and mapping request will be authenticated with the configurations if match a rule
+  "useAuthenticationRules": true
+  // the athentication rules to match
+  "authenticationRules": [
+  { // every rule has a `urlPattern` regex to match
+    "urlPattern": ".*geostore.*",
+    // and a authentication `method` to use (basic, authkey)
+    "method": "basic"
+  }, {
+    "urlPattern": "\\/geoserver.*",
+    "method": "authkey"
+  }
+  "plugins": {
+      // plugins to load for the mobile mode
+      "mobile": [...]
+      // plugins to load for the desktop mode
+      "desktop": [...]
+      // plugins to load for the embedded mode
+      "embedded": [...]
+      // plugins to load for the myMode mode
+      "myMode": [...]
+  }
+],
+  ```
+If you are building your own app, you can choose to create your custom modes or force one of them by passing the `mode` parameter in the query string.
+
+For configuring plugins, see the [Configuring Plugins Section](plugins-documentation) and the [plugin reference page](./api/plugins)