NUnit 2.6.4 source zip is missing files

[CharliePoole]

See this PR: #34

The PR "fixes" the problem by dropping a bunch of tests from the build and was rejected. We should either fix the source zip or drop it entirely, since GitHub already provides a zip of the source.

This can be fixed immediately on the site by removing or updating the file.

[Mailaender]

I can confirm that https://github.com/nunit/nunitv2/releases/download/2.6.4/NUnit-2.6.4-src.zip is both redundant to the GitHub auto-generated one and broken (missing files). However your source ZIP is a lot lighter (4 MB vs 30 MB) as you seem to have unbundled dependencies.

[CharliePoole]

Yes, I think it makes sense to fix it for that reason. I have removed the bad file for now, however.