install git on ubuntu 12.04 not git-core

apt-cache show git-core on ubuntu 12.04 says:
This is a transitional dummy package.  The 'git-core' package has been
renamed to 'git', which has been installed automatically.  This
git-core package is now obsolete, and can safely be removed from the
system if no other package depends on it.
Removes windows dependency to avoid ERROR: TSort::Cyclic: topological sort failed: ["windows", "powershell"]
Removes windows support