refatctoring of some code repetition in spawn_methods

This reverts commit 9c18b6a8.

Fix usage of lambda as a Rack endpoint

These tests are needed only if we are using MiniTest::Spec

minitest/autorun load minitest/spec polluting the global namespace with
the DSL that we don't want on Rails

This reverts commit 22bc12ec.

REASON: We will remove the MiniTest::Spec from Rails and we need these
methods again

Conflicts:
	activesupport/lib/active_support/test_case.rb

The response body needs to respond_to? :each.

Charset should not be appended to image/* type

      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"

Define [], []=, permanent, signed and encrypted as the only allowed methods for the non Raw Cookie classes

fix testcase: ruby-2.0.0 warned unused variables

This reverts commit fba97c96.

Fix missing ending newline in db structure dump:

  When dumping database structure with `rake db:structure:dump` and
using migrations, the resulting file will not end with a newline char.
Although it's not mandatory, it breaks a lot of simple use cases with
programs like cat, more, grep, etc.

  This changes use `puts' instead of `<<' to append migration versions
data to the dump and also split the line where this is happening as it
was a bit long.

warning removed: shadowing outer local variable

Update documentation for yml usage

Fix up/down column change example code formatting

small refactoring, added blob_or_text_colum? in AbstractMysqlAdapter