Some testing fixes.

Added a online category to some tests which require online access.
Saved a copy of CKAN-meta-testkan.zip so that the sanity checker tests are offline.
Fixed KSP.Training test to work on windows as well as linux.
`RelationshipResolver` should always include its input list in the collection that it returns, this means the output of it can be used directly by `ModuleIntaller.InstallList()`.

However if something is already installed, then gosh, I don't know if it should prune it out (which is what we test for here), throw a kraken (probably not, one might be running the resolver to re-generate suggests/recommends), or leave it as-is (which is probably wrong, but `InstallList` skips over already installed mods).

I wish NUnit supported [TAP style TODO tests](http://testanything.org/tap-specification.html), which are acceptable to fail, and awesome when they pass, because this would be a perfect candidate. :)