AS::Callbacks: improved __define_runner performance

::BasicObject always defined in ruby 19

ruby 1.9 returns method names as symbols

Module#name returns nil for anonymous class in ruby 1.9

remove date methods that are present in 1.9 ruby

remove useless 1.8 ruby code from Range#step

AS::Callbacks: improve __define_runner perfomance for non-keyed callbacks.

remove useless 1.8 ruby code from Range#step, because Range#step without block always returns enumerator

* Passing edge information to the views fixes the lack of the edge badge
and sets the appropriate welcome page on edgeguides.rubyonrails.org.
* Changes in the welcome message to hyper link the rails tree based on
the version.
* Mention the Amazon url from where kindlegen can be downloaded.

Fix my name in CHANGELOG.md

remove checks for encodings availability

prompt message for gem ruby-debug19 for console error if ruby-debug19 not found

remove Time._dump and Time._load patching for ruby 1.8

don't call an extra method if options[:tokenizer] is not present

remove deprecated Module#synchronize from ActiveSupport

remove deprecated define_attr_method from ActiveModel::AttributeMethods