add xml parser

samples/xml-test.lua

@@ -0,0 +1,16 @@
+local xml = require "xml"
+
+local test_xml = 
+[[
+<test one="two">
+    <three four="five" four="six"/>
+    <three>eight</three>
+    <nine ten="eleven">twelve</nine>
+</test>
+]]
+
+function on_resume()
+    local parsed = xml:parse(test_xml)
+
+    ui:show_text(parsed.test["@one"])
+end