Export-NUnitReport function was missing a close tag

Failed test cases weren't closing their failure tag, which resulted in the whole file structure being thrown off.  (test-case elements were being nested inside other test-case elements, etc.)
Merge pull request #195 from dlwyatt/NUnitFix

Export-NUnitReport function was missing a close tag
Update CHANGELOG.md
Upping the version to 3.0.1
Updated version in psd1 file
Fixing wrong version in the manifest, publishing new version so I can update it on Nuget/Chocolatey