Allow clean addition of plugins without editing janus

Signed-off-by: Aman Gupta <aman@tmm1.net>

README.markdown

@@ -56,6 +56,12 @@ For example, to override the default color schemes:
     echo color desert  > ~/.vimrc.local
     echo color molokai > ~/.gvimrc.local
 
+If you want to add additional Vim plugins you can do so by adding a
+`~/.janus.rake` like so:
+
+    vim_plugin_task "zencoding", "git://github.com/mattn/zencoding-vim.git"
+    vim_plugin_task "minibufexpl", "git://github.com/fholgado/minibufexpl.vim.git"
+
 ## Updating to the latest version
 
 To update to the latest version of the distribution, just run `rake`

Rakefile

@@ -214,6 +214,11 @@ vim_plugin_task "vwilight" do
   sh "curl https://gist.github.com/raw/796172/724c7ca237a7f6b8d857c4ac2991cfe5ffb18087/vwilight.vim > colors/vwilight.vim"
 end
 
+if File.exists?(janus = File.expand_path("~/.janus.rake"))
+  puts "Loading your custom rake file"
+  import(janus)
+end
+
 desc "Update the documentation"
 task :update_docs do
   puts "Updating VIM Documentation..."