refactor the naming within plugin new generator

Having a method called `full?`, which checks on :full and :mountable
is very confusing. I renamed `full?` to `engine?` and created a `full?`
method that only checks the `:full` option
Use attr_accessor for Rails.{application,cache,logger}
Add periodical-style TOC and navigation to Kindle version of guides
add a notice about loading assets in production mode
Merge pull request #120 from tonytonyjan/patch

add a notice about loading assets in production mode
Correct bad English
Define a generator before referring to it
Introduce Bundler and Gemfiles in a NOTE
correct bad jquery syntax
adding example for f.file_input
adding example for f.file_input
complementary options guidelines for f.file_field and file_field_tag
API reader should look elsewhere for helper instructions
changing tense, since Rails 3.2 has been released
Added overview items to Guides Guidelines prologue
Fixed grammar in a lot of guide prologues.
Fix small grammatical error
Punctuation, capitalization, grammar fixes in rails guides
use :only instead of :except callback option in the controller template

As [Security Guide](http://edgeguides.rubyonrails.org/security.html#whitelists-versus-blacklists)
says, it's better to use `before_filter only: []` instead of `except: []`
so we don't forget to turn the filter off for newly added actions.
Update activesupport/lib/active_support/deprecation/proxy_wrappers.rb

Fix a typo in rdoc (*expect* for *except*)