Make sure castle dir exists before trying to link from it, preventing empty dirs from being created.

lib/homesick.rb

@@ -41,6 +41,12 @@ class Homesick < Thor
 
   desc "link NAME", "Symlinks all dotfiles from the specified castle"
   def link(home)
+    unless castle_dir(home).exist?
+      say_status :error, "Castle #{home} did not exist in #{repos_dir}", :red
+
+      exit(1)
+
+    else
       inside castle_dir(home) do
         files = Pathname.glob('.*').reject{|a| [".",".."].include?(a.to_s)}
         files.each do |path|
@@ -55,6 +61,8 @@ class Homesick < Thor
       end
     end
 
+  end
+
   desc "list", "List cloned castles"
   def list
     inside repos_dir do