Simplify `print_items`
Separate `draw_login_form` from `draw_login`
Reduce length of `print_posts` and `print_boards`

Separate `print_post` and `print_board` from `print_posts` and
`print_boards` respectively.
Bump Rails to 4.1.7

See
http://weblog.rubyonrails.org/2014/10/30/Rails_3_2_20_4_0_11_4_1_7_and_4_2_0_beta3_have_been_released/.
Update gems
Bump RuboCop to 0.27.0
Merge pull request #108 from yous/patch-complexity

Reduce code complexity
Merge pull request #109 from yous/patch-gems

Update gems