mkdir -p ~/.vim/{ftdetect,indent,syntax} && for d in ftdetect indent syntax ; do wget --no-check-certificate -O ~/.vim/$d/scala.vim https://raw.githubusercontent.com/derekwyatt/vim-scala/master/syntax/scala.vim; done
Update
Here is a solution using cURL submitted by Joe:
mkdir -p ~/.vim/{ftdetect,indent,syntax} && for d in ftdetect indent syntax ; do curl -o ~/.vim/$d/scala.vim https://raw.githubusercontent.com/derekwyatt/vim-scala/master/syntax/scala.vim; done