patch creation can now create IPS patches if offsets are below format limit, rearranged files internally

js/worker_crc.js

@@ -0,0 +1,23 @@
+/* Rom Patcher JS v20200502 - Marc Robledo 2016-2020 - http://www.marcrobledo.com/license */
+
+self.importScripts(
+	'./MarcFile.js',
+	'./crc.js'
+);
+
+
+
+self.onmessage = event => { // listen for messages from the main thread
+	var sourceFile=new MarcFile(event.data.u8array);
+
+	self.postMessage(
+		{
+			crc32:crc32(sourceFile, event.data.startOffset),
+			md5:md5(sourceFile, event.data.startOffset),
+			u8array:event.data.u8array
+		},
+		[
+			event.data.u8array.buffer
+		]
+	);
+};