HTML5 validation error with options_from_collection_for_select

Fixes #5908

Conflicts:
	actionpack/CHANGELOG.md

the select method (tag select) forces :include_blank  if is required and no multiple and
display size is one

and display size 1 and not multiple attribute,  Fixes #5908

Fix failing AR test on Oracle

Switch token_tag if block

configuration for active_support and JSON Encoding

Changed /images and /fonts to /assets in the examples of
image_path, image_tag and font_path helpers

[ci skip]

missplelling error in abstract_mysql_adapter

Conflicts:
	activesupport/lib/active_support/callbacks.rb

Comment for active_support's option in application.rb

This reverts commit 667d0bdd, reversing
changes made to 4ae6bab6.

Closes #6274

mispelling errors in render_text_test.rb

Add commas missing in performance tests

Object#try can't call private methods

refactored extracting :size => 'XxY' into an extract_size! method

mispelling error in actionpach changelog

Add #nodoc to initialize_dup and use :method: to document the #dup method.
Relates to issue #6235

Makes it consistent with Relation. Can't see a use for this.