rake -> bin/rake
AM Guide: Should be "different formats".
Cleanup task for informing about hstore
Merge pull request #11584 from Peeja/actionmailer-guide-typo

ActionMailer Guide: Should be "different formats".
Merge pull request #11585 from vipulnsward/hstore_change

Cleanup task for informing about hstore
Allow overriding of all headers from passed environment hash

Allow REMOTE_ADDR, HTTP_HOST and HTTP_USER_AGENT to be overridden from
the environment passed into `ActionDispatch::TestRequest.new`.

Fixes #11590
Privatize non-test method
Use Ruby 2.0 caller_locations instead of caller if available

* we no more have to manipulate the each caller strings by ourselves using caller_locations

* caller_locations runs slightly faster, and creates less objects than good old caller
Benchmark (loading an Engine 1000 times):
  caller: 262.89 ms
  caller_locations: 186.068 ms
Clean up unused associations in AR test model
More unused associations in AR test models
Typo fix

[skip ci] Fixing the typo which is formed a not required link.  Check here http://api.rubyonrails.org/classes/ActionController/Base.html  under paramters section
keeping it under tt tag
change function def self.table_name to self.table_name

change def self.primary_key to self.primary_key

change def self.primary_key to self.primary_key
Merge pull request #11593 from rajcybage/fix_test_models

change function def self.table_name to self.table_name
Merge pull request #11591 from ankit8898/typo

Typo fix [ci skip]
:scissors: [ci skip]
Merge pull request #11341 from arunagw/added-missing-actionview-to-install

Added description in actionview gemspec.
Merge pull request #11582 from steveklabnik/add_bin

rake -> bin/rake
used flat_map instead of map.flatten
Merge pull request #11598 from Karunakar/flat_map1

Used flat_map instead of map.flatten in mas_many_through_associations_test.rb
grab executable from rubygems