Ensure unrelated native.xml files dont cause issues

[ianharrigan]

Its possible (and valid) for certain config files (like native.xml) to exist on the classpath, but are nothing to do with haxeui.

Expected Behavior

These files should be parsed but not cause any issue if they dont contain the correct information.

Current Behavior

Unknown - im fairly certain that they wouldnt cause issues, but this needs to be verified.

Steps to Reproduce (for bugs)

1. add a native.xml to the classpath
2. create content that isnt haxeui related

Additional

It would also be a good time to test how the failure mechanisms work; so creating malformed xml in a native.xml should also not break anything, but possibly issue a warning.