XML to javascript and back - operation should be reversible

[lafar6502]

If you parse an xml document into an object and then use xml2js.Builder to convert the resulting object back to xml, the output should be equivalent to the original xml document. This way it would be much easier to modify xml and save it. Currently the resulting XML is just an xml representation of a javascript object that is totally different from the original xml. An example - xml namespace information gets serialized to something like `

<$ns> urn:hl7-org:v3 effectiveTime

              <value xsi:type="[object Object]" value="[object Object]" unit="[object Object]">
                <$ns>
                  <uri>urn:hl7-org:v3</uri>
                  <local>value</local>
                </$ns>
              </value>
              <interpretationCode code="[object Object]" codeSystem="[object Object]">
                <$ns>
                  <uri>urn:hl7-org:v3</uri>
                  <local>interpretationCode</local>
                </$ns>
              </interpretationCode>

`

for original xml being

`

                                <value xsi:type="PQ" value="145" unit="mm[Hg]"/>
                                <interpretationCode code="N" codeSystem="2.16.840.1.113883.5.83"/>

`

[Leonidas-from-XIV]

Due to the magnitude of options that change the generation of the JS object, it is difficult to support the generation on the same XML that was fed in. But if you feel like submitting PRs, great!

(That said, xsi:type="[object Object]" is definitely a bug)