Add error handler docs.

Author: yajra

documentation.md

@@ -15,6 +15,7 @@
 - Configuration
     - [General Settings](/docs/{{package}}/{{version}}/general-settings)
     - [Debugging Mode](/docs/{{package}}/{{version}}/debugger)
+    - [Error Handler](/docs/{{package}}/{{version}}/error-handler)
 - Engines & Data Sources
 	- [Eloquent](/docs/{{package}}/{{version}}/engine-eloquent)
 	- [Query Builder](/docs/{{package}}/{{version}}/engine-query)

error-handler.md

@@ -0,0 +1,76 @@
+# Error Handler
+
+Laravel DataTables allows you to configure how you want to handle server-side errors when processing your request. 
+Below are the options available for error handling.
+
+## ERROR CONFIGURATIONS
+Configuration is located at `config/datatables.php` under `error` key.
+
+
+- [NULL](#null-error) : `'error' => null`
+- [THROW](#throw-error) : `'error' => 'throw'`
+- [CUSTOM MESSAGE](#custom-message) : `'error' => 'Any custom friendly message'`
+- [TRANSLATION](#custom-message) : `'error' => 'translation.key'`
+
+<a name="null-error"></a>
+## NULL Error
+If set to `null`, the actual exception message will be used on error response.
+
+```json
+{
+	"draw": 24,
+	"recordsTotal": 200,
+	"recordsFiltered": 0,
+	"data": [],
+	"error": "Exception Message:\n\nSQLSTATE[42S22]: Column not found: 1054 Unknown column 'xxx' in 'order clause' (SQL: select * from `users` where `users`.`deleted_at` is null order by `xxx` asc limit 10 offset 0)"
+}
+```
+
+<a name="throw-error"></a>
+## THROW Error
+If set to `'throw'`, the package will throw a `\Yajra\Datatables\Exception`. 
+You can then use your custom error handler if needed.
+
+**Example Error Handler**
+
+Update `app\Exceptions\Handler.php` and register dataTables error exception handler.
+
+```php
+    /**
+     * Render an exception into an HTTP response.
+     *
+     * @param  \Illuminate\Http\Request  $request
+     * @param  \Exception  $exception
+     * @return \Illuminate\Http\Response
+     */
+    public function render($request, Exception $exception)
+    {
+        if ($exception instanceof \Yajra\Datatables\Exception) {
+            return response([
+                'draw'            => 0,
+                'recordsTotal'    => 0,
+                'recordsFiltered' => 0,
+                'data'            => [],
+                'error'           => 'Laravel Error Handler',
+            ]);
+        }
+
+        return parent::render($request, $exception);
+    }
+```
+
+<a name="custom-message"></a>
+## Custom Message
+If set to `'any custom message'` or `'translation.key'`, this message will be used when an error occurs when processing the request.
+
+```json
+{
+	"draw": 24,
+	"recordsTotal": 200,
+	"recordsFiltered": 0,
+	"data": [],
+	"error": "any custom message"
+}
+```
+
+