Add docs for print column.

Author: jidagob

print-column.md

@@ -2,11 +2,22 @@
 
 You can print a column customised header if manually set.
 
-<a name="blade"></a>
-## Print Column
+<a name="print-column-with-title"></a>
+## Print Columns with Custom Title
 
 ```php
-	protected $printColumns = [
-        ['data' => 'email', 'title' => 'Registered Email],
-    ];
+protected $printColumns = [
+    ['data' => 'name', 'title' => 'Name'],
+    ['data' => 'email', 'title' => 'Registered Email'],
+];
+```
+
+<a name="print-column"></a>
+## Print Columns
+
+```php
+protected $printColumns = [
+    'name',
+    'email',
+];
 ```