Add slicer-nightly (3D Slicer nightly build) (#4225)
Add slicer-nightly (3D Slicer nightly build) (#4225)

* Add slicer-nightly

* Update slicer-nightly.rb

* Update slicer-nightly.rb

mahori/homebrew-versions,yurikoles/homebrew-versions,lantrix/homebrew-versions,victorpopkov/homebrew-versions,pkq/homebrew-versions,yurikoles/homebrew-versions,FinalDes/homebrew-versions,Ngrd/homebrew-versions,victorpopkov/homebrew-versions,lantrix/homebrew-versions,404NetworkError/homebrew-versions,caskroom/homebrew-versions,pkq/homebrew-versions,404NetworkError/homebrew-versions,caskroom/homebrew-versions,Ngrd/homebrew-versions,rogeriopradoj/homebrew-versions,FinalDes/homebrew-versions,rogeriopradoj/homebrew-versions,mahori/homebrew-cask-versions