Change Nuget.Core.dll to NuGet.Core.dll in build script

[nathansoz]

We were finding that NuGet.Core wasn't able to be resolved on our linux systems when using Cake because it was getting copied into the nuget package as Nuget.Core.dll. It turns out that the resolution of this file is case sensitive on linux. I believe this issue may also have been encountered by @Silvenga in issue #623

[gep13]

@nathansoz thanks for the contribution! The change itself looks good.

Would it be possible to alter this PR slightly to create a new branch, and rebase the change on the develop branch, rather than have the merge in your commit history? This is as per our contributing document: https://github.com/cake-build/cake/blob/develop/CONTRIBUTING.md

Thanks!

[nathansoz]

Sorry about that! I believe I've done the right thing now. Let me know if it isn't correct.

[gep13]

@nathansoz this looks better. I am going to go ahead and merge this change in, this it is a relatively small change. However, for any future changes, can I please ask that you first create a branch, from develop, to do your work on, and then create the Pull Request from that branch, into cake/develop?

This makes getting changes etc done on the branch much easier. Thanks again for your contribution, we really appreciate it! 👍

[nathansoz]

Ah got it. I did make a branch, but I merged it into my develop branch first. Sorry!

[gep13]

@nathansoz not a problem at all.