Fix curl command to support GitHub's new redirect

Closes #120.

Author: tpope

README.markdown

@@ -9,7 +9,7 @@ private directories.
 Install to `~/.vim/autoload/pathogen.vim`. Or copy and paste:
 
  mkdir -p ~/.vim/autoload ~/.vim/bundle; \
- curl -Sso ~/.vim/autoload/pathogen.vim \
+ curl -LSso ~/.vim/autoload/pathogen.vim \
   https://raw.github.com/tpope/vim-pathogen/master/autoload/pathogen.vim
 
 If you're using Windows, change all occurrences of `~/.vim` to `~\vimfiles`.