add swift flatbuffers

flatbuffers/Documentation.docc/Resources/code/swift/swift_code_11.swift

@@ -0,0 +1,11 @@
+import FlatBuffers
+import Foundation
+
+func run() {
+  // create a ByteBuffer(:) from an [UInt8] or Data()
+  let buf = [] // Get your data
+  var byteBuffer = ByteBuffer(bytes: buf)
+  // Get an accessor to the root object inside the buffer.
+  let monster: Monster = try! getCheckedRoot(byteBuffer: &byteBuffer)
+  // let monster: Monster = getRoot(byteBuffer: &byteBuffer)
+}