Tools to clean up xml files abound in the internet. But if you have a need to do batch processing of a bunch of files or just the plan joy of doing it from the command line then you can use xmllint. If you are using openSUSE, Ubuntu or Linux Mint 10 (and many other Linux distro) then this is come pre-installed. xmllint is flexible and have way more features than shown below but this should give you a taste of the tools usefulness. So to tidy up an xml file do:
~ts
xmllint –format ugly.xml –output pretty.xml
~ts
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