Added public files

Roughly added all public files. Probably missed some, though.
diff --git a/sys/xml.h b/sys/xml.h
new file mode 100644
index 0000000..e630638
--- /dev/null
+++ b/sys/xml.h
@@ -0,0 +1,10 @@
+#ifndef XML_H__
+#define XML_H__ 1
+
+#define XML_TAG_NAME                    0 /* Name of the current tag */
+#define XML_TAG_ATTRIBUTES              1 /* Atttributes of the current tag */
+#define XML_TAG_CONTENTS                2 /* Contents of the current tag */
+
+#define XML_TAG_SIZE                    3
+
+#endif