doctor: restore some line breaks

Library/Homebrew/cmd/doctor.rb

@@ -666,6 +666,7 @@ def check_for_linked_kegonly_brews
     EOS
 
     puts *warnings.keys.collect { |f| "    #{f}" }
+    puts
   end
 end
 
@@ -746,6 +747,7 @@ def check_missing_deps
   if s.length > 0
     ohai "You should brew install these missing dependencies:"
     puts s
+    puts
   end
 end
 
@@ -754,6 +756,7 @@ def check_git_status
   if system "/usr/bin/which -s git" and not `#{status_cmd}`.empty?
     ohai "You have uncommitted modifications to Homebrew core"
     puts "Unless you know what you are doing, you should: git reset --hard"
+    puts
   end
 end