Needs a method for writing XML to an OutputStream

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= problem =
There is no simple way to write a scala.xml.Node to an java.io.OutputStream.

= analysis =
Quite often you have an existing Java library or framework which gives you an java.io.OutputStream which you are supposed to write to.

Doing so from Scala when you have XML data in a scala.xml.Node is currently non-trivial if you want to get Unicode encoding right.
You could wrap the OutputStream with an OutputStreamWriter and use the current XML.write method, but then you need to specify the same encoding twice, and remember to flush the OutputStreamWriter.

= enhancement recommendation =
Add a method to scala.xml.XML with a signature like this:

def write(os: java.io.OutputStream, node: Node, enc: String, xmlDecl: Boolean, doctype: DocType) : Unit

(It could be named "save" as well.)

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Imported From: https://issues.scala-lang.org/browse/SI-4286?orig=1
Reporter: Mikael Ståldal (mikaelstaldal)

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@SethTisue said:
The scala-xml library is now community-maintained. Issues with it are now tracked at https://github.com/scala/scala-xml/issues instead of here in the Scala JIRA.

Interested community members: if you consider this issue significant, feel free to open a new issue for it on GitHub, with links in both directions.