Fix bug when install.sh is not called from current directory

vimrc

@@ -45,7 +45,9 @@ set showmatch
 set laststatus=2 " Always display statusline
 set background=dark
 let g:gruvbox_contrast_dark='hard'
-colorscheme gruvbox
+if filereadable( expand("$HOME/.vim/bundle/gruvbox/colors/gruvbox.vim") )
+	colorscheme gruvbox
+endif
 
 " Indentation
 set tabstop=4