Preparing for 3.0.11 release
bump up rack version to the one that includes the Hash DoS fix
Merge pull request #4246 from amatsuda/hashdos_30

bump up rack version to the one that includes the Hash DoS fix
Fixed failing test for ruby-1.8.7-p357

See #4292
Merge pull request #4372 from arunagw/fixed_failing_test

Fixed failing test
Merge pull request #4514 from brainopia/update_timezone_offets

Update time zone offset information
Bugfix circular reference while saving has_one relationship
Test for circular reference while saving has_one relationship
fix output safety issue with select options
add AS::SafeBuffer#clone_empty
use AS::SafeBuffer#clone_empty for flushing the output_buffer
Merge commit 'v3.0.11' into 3-0-stable
updating RAILS_VERSION
Fixed typo in composed_of example with Money#<=>, was comparing amount itself instead of other_money.amount
Ensure [] respects the status of the buffer.
Merge branch '3-0-stable-security' into 3-0-12

* 3-0-stable-security:
  Ensure [] respects the status of the buffer.
  use AS::SafeBuffer#clone_empty for flushing the output_buffer
  add AS::SafeBuffer#clone_empty
  fix output safety issue with select options
bumping to 3.0.12
Merge branch '3-0-12' into 3-0-stable

* 3-0-12:
  bumping to 3.0.12
  Ensure [] respects the status of the buffer.
  updating RAILS_VERSION
  use AS::SafeBuffer#clone_empty for flushing the output_buffer
  add AS::SafeBuffer#clone_empty
  fix output safety issue with select options
Stop SafeBuffer#clone_empty from issuing warnings

Logic in clone_empty method was dealing with old @dirty variable, which
has changed by @html_safe in this commit:
https://github.com/rails/rails/commit/139963c99a955520db6373343662e55f4d16dcd1

This was issuing a "not initialized variable" warning - related to:
https://github.com/rails/rails/pull/5237

The logic applied by this method is already handled by the [] override,
so there is no need to reset the variable here.
fixed test when running with latest 1.8.7-p357 and ree