Merge pull request #11088 from nolman/nolman/scaffold-fix

fix deprecation warning in scaffold controllers
Change reference to all to scoped instead.

In #11088, `#to_a` was added to remove a deprecation around using
`#all`. I merged, but it really should have been `#scoped` instead, as
that's the preferred replacement.
restore correct scaffold generation
Merge pull request #11093 from nolman/restoring-scaffold-generation

restore correct scaffold generation
We are now rails 4 [skip-ci]
removed unnecessary mapping for on options

Right before that in `assert_valid_transaction_action` method we make
sure that `options[:on]` contains values from `ACTIONS` array
(`[:create, :destroy, :update]`) and nothing more (i.e. it could not
contain strings or something else, otherwise the error is raised).

Also I've polished some docs.
Comment typo
Fixed menu section's location (guides)
Merge pull request #11097 from ryancw/patch-2

ActionView flows comment typo
Merge pull request #11098 from vredniy/master

Fixed menu section's location (guides)
Improve the testing guide [ci skip]

Improve the "Testing Rails Applications" guide adding a section for
testing helpers and a little note about associations with ActiveRecord
and YAML fixtures.

Also add a link to Fixture Builder ; yet another replacement for
fixtures such as Machinist or FactoryGirl.
Merge pull request #11095 from vipulnsward/rails_4_docs

We are now rails 4
Merge pull request #11096 from akalyaev/remove-unnecessary-mapping

removed unnecessary mapping for on options
change id="errorExplanation" to id="error_explanation" to match the generated files
Fix another "error_explanation" css class in guides [ci skip]
Merge branch 'error-explanation'

Closes #11077 [ci skip]
Merge pull request #11046 from arunagw/verbose_mode_on

Verbose mode on when running tests
Merge pull request #11000 from sbeckeriv/accept_header

Fix undefined method `ref' for nil:NilClass for bad accept headers
Fix typo in docs. HABTM associations should use a pluralized name
Merge pull request #11105 from mariozig/correct-documentation

Fix typo in docs. HABTM associations should use a pluralized name [ci skip]