Fix NUnit task on Windows
Fix NUnit task on Windows

When testing for the NUnit executable we added ToolPath twice which
caused us not to find nunit-console in the ToolPath location.
Instead we tried to use the local directory. This change fixes this
problem.

gmartin7/libpalaso,sillsdev/libpalaso,tombogle/libpalaso,ermshiperete/libpalaso,andrew-polk/libpalaso,glasseyes/libpalaso,gtryus/libpalaso,glasseyes/libpalaso,glasseyes/libpalaso,ddaspit/libpalaso,tombogle/libpalaso,gmartin7/libpalaso,tombogle/libpalaso,sillsdev/libpalaso,gtryus/libpalaso,sillsdev/libpalaso,gtryus/libpalaso,ddaspit/libpalaso,gmartin7/libpalaso,ermshiperete/libpalaso,andrew-polk/libpalaso,andrew-polk/libpalaso,ermshiperete/libpalaso,sillsdev/libpalaso,gtryus/libpalaso,ermshiperete/libpalaso,tombogle/libpalaso,gmartin7/libpalaso,andrew-polk/libpalaso,ddaspit/libpalaso,glasseyes/libpalaso,ddaspit/libpalaso