Fixes #3678

This fix causes the AWDwR test to go back to being green on Rails master.

Fix regression introduced by 38d26b0c

Cleanup of databases.rake psql env variables

Fixed typo: expect -> expected

Reason: After another round of discussion, it has been
decided to let interpolation deal with unsafe strings
as it should do.

This reverts commit d57d8098.

allow people to set a local .Gemfile so that things like ruby-debug are not required for regular development

This reverts commit 0e407a90, reversing
changes made to 533a9f84.

Conflicts:

	activerecord/lib/active_record/connection_adapters/abstract/schema_statements.rb
	activerecord/test/cases/migration_test.rb

This reverts commit 81fad6a2, reversing
changes made to 23101de2.

Conflicts:

	activerecord/test/cases/migration_test.rb

Move schema_format :sql config setting from test.rb to application.rb

I've moved the schema_format :sql config setting to application.rb because you would
never enable this only for the test environment. If you use database constraints
or database specific data types you would want all of your environments to use them.

Fix impractical I18n lookup in nested fields_for

It should be @calculated_ip not @calculate_ip

We are using @calculated_ip. 
@calculate_ip is no where used

No need to `readlines` then `join`, just use `read` ❤

same as 4c1a1933

Fixes for Request#remote_ip (no middleware, all proxies)

CSS fix to prevent error output from being breaking out of body element.

Becomes includes errors

This commit contains a simple failing test that demonstrates the behaviour we expect, and a fix. When using `becomes` to transform the type of an object, it should retain any error information that was present on the original instance.

Unused variable removed

This reverts commit 8d1a2b3e, because I have fixed the issues this commit caused in the next commit.

schema_format :sql should behave like schema_format :ruby