Extract with_example_table into helper method.

This setups the helper method which other tests can benefit from.
fix log_tags request object grammar
Fix for digestor to consider variants for partials -- this still needs more testing!!
Log the full path, including variant, that the digestor is trying to find
Digestor should just rely on the finder to know about the format and the variant -- trying to pass it back in makes a mess of things (oh, and doesnt work)
Update test helper to use latest Digestor API
Swapped parameters of assert_equal in assert_select
Adding active_model in Rails::Info
Clean up tables after each test.

Follow-Up to https://github.com/rails/rails/pull/14400

This ensures that all tables are removed after each test and thereby
allowing us to run the tests in a random order.
Remove sqlite3 lines from .gitignore if the application is not using sqlite3.
Check if any sqlite files are not included in the gitignore

If the sqlite file name change in future version we this regexp should
catch
Fix date_select option overwriting html classes

with_css_classes: true option overwrites other html classes.
Concatenate day month and year classes rather than overwriting.
- Rename `increment_or_decrement` to an apt `set_cache_value` since it actually doesn't increment/decrement in localstore.
use ARel factory methods for building AST nodes

This abstracts us from the actual construction of the nodes
do not rely on method_missing hitting arel

arel methods are not supposed to be public API for ActiveRecord
synchronize changelogs and 4.1 release notes. [ci skip]

Conflicts:
	actionpack/CHANGELOG.md
	activerecord/CHANGELOG.md
	activesupport/CHANGELOG.md
	railties/CHANGELOG.md
update comments to reflect that options support is not available
Fix Generation of proper migration when
  ActiveRecord::Base.pluralize_table_names = false.

  Previously, generation a migration like this:

      rails g migration add_column_name_to_user name

  would not generating the correct table name.

Fixes #13426.
clarify CHANGELOG [ci skip].
Refactored code to depend on connection handler's #with_connection instead of #connection.

Any place that called #connection that did not store it in some field was changed to use #with_connection because #with_connection will create a connection, run the block that needs that connection, and then let go of the connection so that connections are held onto.