add 'bundle_path' hidded preference

Author: DanielKehoe

templates/layout.erb

@@ -98,7 +98,11 @@ end
 # >-----------------------------[ Run 'Bundle Install' ]-------------------------------<
 
 say_wizard "Installing gems. This will take a while."
-run 'bundle install --without production'
+if prefs.has_key? :bundle_path
+  run "bundle install --without production #{prefs[:bundle_path]}"
+else
+  run 'bundle install --without production'
+end
 
 # >-----------------------------[ Run 'After Bundler' Callbacks ]-------------------------------<