[Active Record] Renamed private methods create_record and update_record

 This is to ensure that they are not accidentally called by the app code.
 They are renamed to _create_record and _update_record respectively.
 Closes #11645
PostgreSQL and SQLite, remove varchar limit. [Vladimir Sazhin & Toms Mikoss & Yves Senn]

There is no reason for the PG adapter to have a default limit of 255 on :string
columns. See this snippet from the PG docs:

    Tip: There is no performance difference among these three types, apart
    from increased storage space when using the blank-padded type, and a
    few extra CPU cycles to check the length when storing into a
    length-constrained column. While character(n) has performance
    advantages in some other database systems, there is no such advantage
    in PostgreSQL; in fact character(n) is usually the slowest of the
    three because of its additional storage costs. In most situations text
    or character varying should be used instead.
test, show current adapter behavior for `add_column limit: nil`.

This is an illustration of https://github.com/rails/rails/pull/13435#issuecomment-33789752
Removing the limit from the PG and SQLite adapter solves the issue.
MySQL is still affected by the issue.
Use sass-rails 4.0.3
Declare the assets dependency
Merge pull request #11650 from prathamesh-sonpatki/rename

Renamed private methods _create_record and _update_record
Add CHANGELOG entry for #11650 [ci skip]
Fix the test defining the models in the right place
sprockets-rails was released
Merge pull request #14579 from senny/pg/remove_string_limit

PostgreSQL, remove varchar limit.

Conflicts:
	activerecord/CHANGELOG.md
W3C CSP document moved to gihub.io URL [ci skip]

The old link https://dvcs.w3.org/hg/content-security-policy/raw-file/tip/csp-specification.dev.html is now being soft redirected to this new URL
Merge pull request #14612 from acallaghan/patch-1

W3C CSP document moved to gihub.io URL [ci skip]
Use SVG version of travis build status badge [skip ci]
Merge pull request #14623 from t3chnoboy/master

Use SVG version of travis build status badge [ci skip]
Fix setup of adding _flash_types test.

Adding flash types to a controller within any of the tests will result
in a global state change of the controller under test.

This patch will prevent state leaks and allow us to run the test in random order.
Merge pull request #14614 from tgxworld/fix_add_flash_types_test

Fix setup of adding _flash_types test.
Added OS X specific commands to installation guide [ci skip]
Recommended using homebrew for installing MySQL and PostgreSQL
fix CollectionProxy delete_all documentation

This method no longer returns an array of all records that
have been removed. Correct documentation to reflect this change.

See issue 14546
Merge pull request #14626 from eileencodes/fix_incorrect_collection_proxy_delete_all_documentation

fix CollectionProxy delete_all documentation
Remove unused `subclass_controller_with_flash_type_bar` var from flash test.