In the Installation section of README.md there's a table of installation commands for users of the NeoBundle, Vundle, Vim-plug, Pathogen, and Dein plugin managers.

The Pathogen example references the following command:

git clone git://github.com/wellle/targets.vim.git ~/.vim/bundle/targets.vim

Unfortunately, GitHub turned off the git protocol. SeeImproving Git protocol security on GitHub.

The example should be changed to use a supported URL scheme such as "https://" or "ssh://".