update gems and fix tests

Guardfile

@@ -1,20 +1,6 @@
 # A sample Guardfile
 # More info at https://github.com/guard/guard#readme
 
-## Uncomment and set this to only include directories you want to watch
-# directories %w(app lib config test spec features) \
-#  .select{|d| Dir.exists?(d) ? d : UI.warning("Directory #{d} does not exist")}
-
-## Note: if you are using the `directories` clause above and you are not
-## watching the project directory ('.'), then you will want to move
-## the Guardfile to a watched dir and symlink it back, e.g.
-#
-#  $ mkdir config
-#  $ mv Guardfile config/
-#  $ ln -s config/Guardfile .
-#
-# and, you'll have to watch "config/Guardfile" instead of "Guardfile"
-
 guard :minitest do
   # with Minitest::Unit
   watch(%r{^test/(.*)\/?test_(.*)\.rb$})