Vim colorscheme Mustang

I was having some issues setting up a custom color scheme for vim.

Download a colorsheme e.g. mustang from here move it to ~/.vim/colors
In your ~/.vimrc add line
       colorscheme mustang
I was getting

  Error detected while processing /home/morteza/.vimrc:
  line    2:
  E185: Cannot find color scheme mustang
  Press ENTER or type command to continue

To fix this rename
Mustang_Vim_Colorscheme_by_hcalves.vim to mustang.vim

So you get rid of the error but the coloring doesn't work, to fix it you need to add the following line to your ~/.vimrc

         set t_Co=256

Enjoy a cool coloring for your vim!