Clear url helper methods when routes are reloaded

Clear url helper methods when routes are reloaded by removing the
methods explicitly rather than just clearing the module because it
didn't work properly and could be the source of a memory leak.

Closes #8488.
Don't use 1.9 hash syntax on 3-2-stable
Remove unicode character encoding from ActiveSupport::JSON.encode

The encoding scheme (e.g. ☠ -> "\u2620") was broken for characters
not in the Basic Multilingual Plane.  It is possible to escape them
for json using the weird encoding scheme of a twelve-character
sequence representing the UTF-16 surrogate pair (e.g. '𠜎' ->
"\u270e\u263a") but this wasn't properly handled in the escaping code.
Since raw UTF-8 is allowed in json, it was decided to simply pass
through the raw bytes rather than attempt to escape them.

Backport of https://github.com/zbskii/rails/commit/9ace3a8820a5270f9b3f37b593f8bbea3e940f73

Conflicts:

	activesupport/CHANGELOG.md
	activesupport/lib/active_support/json/encoding.rb
	activesupport/test/json/encoding_test.rb
Use 1.8 style hash in json encoding test
Backport #8522, Keep index names when using  with sqlite3

Conflicts:

	activerecord/CHANGELOG.md
	activerecord/lib/active_record/connection_adapters/sqlite3_adapter.rb
	activerecord/test/cases/migration/rename_column_test.rb
Merge pull request #8558 from senny/backport_3489

Backport #8522, Keep index names when using  with sqlite3
Serialized attribute can be serialized in an integer column

Fix #8575

Conflicts:
	activerecord/CHANGELOG.md
	activerecord/lib/active_record/attribute_methods/serialization.rb
	activerecord/test/cases/serialized_attribute_test.rb
	activerecord/test/models/person.rb
Add release date of Rails 3.2.9 to documentation

Conflicts:
	actionpack/CHANGELOG.md
	activerecord/CHANGELOG.md
	activesupport/CHANGELOG.md
updating the changelog for the CVE
updating the changelogs
updating changelog
CVE-2012-5664 options hashes should only be extracted if there are extra parameters
Merge branch '3-2-sec' into 3-2-secmerge

* 3-2-sec:
  CVE-2012-5664 options hashes should only be extracted if there are extra parameters
  updating changelog
  updating the changelogs
  updating the changelog for the CVE
  Add release date of Rails 3.2.9 to documentation

Conflicts:
	actionmailer/CHANGELOG.md
	actionpack/CHANGELOG.md
	activemodel/CHANGELOG.md
	activerecord/CHANGELOG.md
	activeresource/CHANGELOG.md
	activesupport/CHANGELOG.md
	railties/CHANGELOG.md
bumping version to 3.2.10
backport #8616, quote column names in generated fixture files

Conflicts:

	railties/CHANGELOG.md
	railties/lib/rails/generators/test_unit/model/model_generator.rb
	railties/lib/rails/generators/test_unit/model/templates/fixtures.yml
	railties/test/generators/model_generator_test.rb
Merge pull request #8618 from senny/backport_8612

backport #8616, quote column names in generated fixture files
Fix `validates_presence_of` with `:allow_nil` or `:allow_blank` options.

Fix #8621

[Colin Kelley + Rafael Mendonça França]
Revert "Fix `validates_presence_of` with `:allow_nil` or `:allow_blank` options."

This reverts commit 93366c7c913bf0883f140fa782d3e198593477be.

REASON: This is backward incompatible. Also this behavior is documented
on the guides.
backport #8662, charset should not be appended for `head` responses

      1) Failure:
    test_head_created_with_image_png_content_type(RenderTest) [test/controller/render_test.rb:1238]:
    Expected: "image/png"
      Actual: "image/png; charset=utf-8"
Merge pull request #8665 from senny/8661_should_not_append_charset_if_already_present

backport #8662, charset should not be appended for `head` responses