escape command for remote hook

Running remote commands we have a policy of wrapping
those into a `bash -l -c ""`. I'm no more completely
sure about this approach.
Moreover as per issue #492 complex command may broke
and the user has no way to manage himself the escaping.

ATM I'm trying to do a programmatic hidden escape of
the user input specified command.

lib/wordmove/hook.rb

@@ -102,7 +102,7 @@ def self.run(commands, options, simulate = false)
           return true if simulate
 
           stdout, stderr, exit_code =
-            copier.exec!("bash -l -c 'cd #{wordpress_path} && #{command}'")
+            copier.exec!("bash -l -c 'cd #{wordpress_path} && #{Shellwords.escape(command)}'")
 
           if exit_code.zero?
             logger.task_step false, "Output: #{stdout}"