FIX silverstripe#8 Add config option for sequential uploads

setting Component option 'sequentialUploads' to true will upload files
one by one in the order they were selected

README.md

@@ -44,6 +44,7 @@ The available configuration options are:
 * 'fieldsClassBlacklist' : array of string referencing types (ClassName) of fields that wont be available for editing
 * 'fieldsNameBlacklist' : array of string referencing the names of fields that wont be available for editing
 * 'folderName' : name of the folder where the images should be uploaded
+* 'sequentialUploads' : boolean, if true files will be uploaded one by one
 
 Each option can be set through the component's method setConfig( $reference, $value )
 In addition, some configuration option can be set more specifically via individual methods:

code/GridFieldBulkImageUpload.php

@@ -22,7 +22,8 @@ class GridFieldBulkImageUpload implements GridField_HTMLProvider, GridField_URLH
 		'editableFields' => null,
 		'fieldsClassBlacklist' => array(),
 		'fieldsNameBlacklist' => array(),
-		'folderName' => 'bulkUpload'
+		'folderName' => 'bulkUpload',
+    'sequentialUploads' => false
 	);
 
 	/**
@@ -67,6 +68,12 @@ function setConfig ( $reference, $value )
 		{
 			$value = array_unique( array_merge($value, $this->forbiddenFieldsClasses) );
 		}
+
+    //sequentialUploads true/false
+    if ( $reference == 'sequentialUploads' && !is_bool($value) )
+		{
+      $value = false;
+		}
 
 		$this->config[$reference] = $value;
 	}

code/GridFieldBulkImageUpload_Request.php

@@ -199,7 +199,8 @@ public function index()
 		$uploadField->removeExtraClass('ss-uploadfield');
 
 		$uploadField->setTemplate('AssetUploadField');
-		$uploadField->setConfig('downloadTemplateName','GridFieldBulkImageUpload_downloadtemplate');
+		$uploadField->setConfig('downloadTemplateName','GridFieldBulkImageUpload_downloadtemplate');   
+    $uploadField->setConfig('sequentialUploads', $this->component->getConfig('sequentialUploads'));
 
 
 		$uploadField->setConfig('url', $this->Link('upload'));