clarify singular and plural routes

Found the wording on line 158 somewhat confusing. Added short example to clarify.
Update guides/source/active_record_querying.md

Fix missing `ORDER BY id ASC` for Client.first(2);
Uppercase the little y in the SQL equivalent of the Client.last(2).
Fix bug in code example from layouts and rendering guide

The code in 2.3.2 assumed that render has an alert option like
redirect_to to create a flash alert message, but it doesn't.
Corrected link anchor and added colons for continuity
improve grammar describing ActionDispatch::Cookies::CookieJar#delete
improve grammar describing ActionDispatch::Cookies::CookieJar#delete
Update the "upgrading" guide for people coming from 3.0 and 3.1. The latest versions for 3.1 and 3.2 are now 3.2.12 and 3.1.11 respectively.
Typo fix.
Link is not relevant anymore

Cannot find the screencast on the internet, guess it was removed
Added documentation for beginning_of_minute and end_of_minute to Active Support Core Extensions guide
Wrap `around_action` word with <code> tag
Update guide doc to use migration shortcuts
BELONGS TO ASSOCIATION | Typo fix
Typo fix
Expand order(:symbol) to "table".symbol to prevent broken queries on PG.
Fixes #9275.

When `#order` is called with a Symbol this patch will prepend the quoted_table_name.
Before the postgresql adapter failed to build queries containg a join and an order
with a symbol.

This expansion happens for all adapters.
Fix deletion of empty directories:

1. When comparing the directory to delete against the top level
   cache_path, use File.realpath to make sure we aren't comparing two
   unequal strings that point to the same path. This occurs, for
   example, when cache_path has a trailing slash, which it does in the
   default Rails configuration. Since the input to
   delete_empty_directories never has a trailing slash, the comparison
   will never be true and the top level cache directory (and above) may
   be deleted. However…

2. File.delete raises EPERM when trying to delete a directory, so no
   directories have ever been deleted. Changing the code to Dir.delete
   fixes that.
No need to send public methods
Merge pull request #9414 from senny/9275_order_with_symbol_and_join

Expand order(:symbol) to "table".symbol to prevent broken queries on PG.
Allow both a path and an option on root in config/routes
Merge pull request #9441 from rubys/master

This is a small thing, motivated by https://github.com/rails/rails/issues/9419