use pretty xml in expect tests

[Adrian Cole]

We use single-line xml when emitting commands. This helps keep wire logs sane, for example. However, in test cases (and code reviews) single-line xml is hard to read. Let's investigate a way to ensure that Expect and MockWebServer tests can assert that our serialization creates single-line xml docs, yet doesn't require src/test/resources files to be single-line. Probably, this would be as simple as a regex replace command.

jclouds/jclouds@e7bdfa6#providers-ultradns-ws-src-test-resources-delete_lbpool-xml-P3