This option was added on cb6f8393
renaming the :wait_timeout option.

Fix build http://travis-ci.org/#!/rails/rails/jobs/1413405

This reverts commit fa6d921e.

Reason: Not a fan of such massive changes. We usually close such changes
if made to Rails master as a pull request. Following the same principle
here and reverting.

[ci skip]

For future reference, this is the regex I used: ^\s*#\s*\n(?!\s*#). Replace
with the first match, and voilà! Note that the regex matches a little bit too
much, so you probably want to `git add -i .` and go through every single diff
to check if it actually should be changed.

escape_hstore uses quotation marks around keys and values only if it
seems necessary. However, it currently breaks in the presence of some
non-ASCII characters. Instead of trying to guess exactly which
characters are safe, it seems better to always use quotes.

Restored ability to identify ID and Sequence from tables relying on a nonmatching sequence default value for PK.

Connection pools are 1:1 with pids.

The `add_index` method now supports a `where` option that receives a
string with the partial index criteria.

    add_index(:accounts, :code, :where => "active")

    Generates

    CREATE INDEX index_accounts_on_code ON accounts(code) WHERE active