make the duplicate code more similar
reduce duplication somewhat
Use Ruby on Rails Coding Conventions for code examples in the guides

* Indent after private/protected
* Ruby >= 1.9 syntax for hashes
* Prefer method { do_stuff } instead of method{do_stuff} for single-line blocks.

[ci skip]
use polymorphic proxies to remove duplicate code
hm:t join tables may not have a primary key
Merge pull request #12155 from jetthoughts/reformat_guides_code_examples

Use Ruby on Rails Coding Conventions for code examples in the guides
Use MiniTest::Unit::TestCase instead of Minitest::Test

Since Rails 4.0.x is depending on Minitest 4.x, the constant won't be
available so the gist won't run.

[ci skip]
do not break params filtering on nil values

closes #12149
Fix fixtures regression that required table names to map to classes only, not class names
Allow Relation#from to accept other relations with bind values.
Blacklist refferenced in docs is actually whitelist
The docs refference a blacklist, but really what's being described
is a whitelist. Anything that matches the constraint gets through to
the path.
Change documentation to consistently refer to the same object
The documentation in this section is referring to a profile,
so the resource that's created should probably also be a
profile of some sort.
Typo in Changelog.
Merge pull request #12164 from rywall/patch-1

Typo in Changelog. [ci skip]
form_for - fix :namespace and :as options clash

:as option should not overwrite :namespace option when
generating html id attribute of the form element. id should be prefixed
by specified namespace even if :as option is present

Add test case showing the issue and code fixing it
[ci skip] Change link name of Rails i18n wiki.

Actually it's Ruby i18n link.
Merge pull request #12166 from JuanitoFatas/doc-patch-1

[ci skip] Change link name of Rails i18n wiki.
Improves a sentence in guides/security

Changed "... books make this wrong" to "... books get this wrong"
Merge pull request #12157 from robin850/patch-9

Use MiniTest::Unit::TestCase instead of Minitest::Test  [ci skip]
Fixed API task file

1. As we have vendor in AV only
2. No more vendor in AC
3. No vendor folder in AR