ISOTaggedField#dump outputs invalid XML

[barspi]

When using TaggedSequencePackager and ISOTaggedField, the dump method produces output such as

<isomsg id="48">
   <!-- org.jpos.tlv.packager.TaggedSequencePackager -->
   <0002><field id="1" value="SUR"/></0002>
   <0003><field id="2" value="SUR"/></0003>
   <0023><field id="3" value="CT6"/></0023>
   <0052><field id="4" value="210"/></0052>
...

This is invalid, badly-formed XML: the tags of type <number> are invalid, and would prevent the XMLPackager and other XML tools from parsing the output of the dump method.

A suggested fix would be to dump them like:

<field id="4" type="tagged" tag="0052" value="210" />

or the type attribute could be "tlv"

NOTE This could be a breaking change for code that expects the old output! Please comment