Fix DB Console tests 

The build is broken: https://travis-ci.org/rails/rails/builds/15824530

This commit fixes it.

The problem: Sqlite expects the `database` part to be an absolute path. That prompted this change to be committed to master: https://github.com/rails/rails/commit/fbb79b517f3127ba620fedd01849f9628b78d6ce

This change provides correct behavior. Unfortunately tests were introduced in https://github.com/rails/rails/commit/971d5107cd4cd08c22a85d34546f4ba03ed5c925 that were relying on the incorrect behavior. We can avoid the fix by changing to another database url such as `mysql` or `postgresql`

In addition to fixing the failure, the assertions are changed so that the "expected" value comes before "actual" value.
Use Full path to sqlite database in tests
Merge pull request #13443 from schneems/schneems/fix-master-tests

Fix DB Console tests
Add comments with urls for email previews
Use the same enum definition in the docs and in the comments [ci skip]
fix quoting non-strings

Closes #13444
Merge pull request #13451 from dmathieu/quoting_non_strings

Fix typecasting array of integers
CHANGELOG entry for #13451. [ci skip]
Add missing av/railtie require
Merge pull request #13457 from strzalek/add-missing-av-railtie

Add missing av/railtie require
added test cases for Resolver#connection_url_to_hash
Merge pull request #13446 from kuldeepaggarwal/resolver-test-cases

Resolver test cases
On destroying do not touch destroyed belongs to association.

Fixes: #13445
Merge pull request #13455 from jetthoughts/13445_fix_touch_destroyed_record

On destroying do not touch destroyed belongs to association.
Fix comment example in AR enum [ci skip]
Tell how to Create a Database in Error Message

Currently if you attempt to use a database that does not exist  you get an error:

```
PG::ConnectionBad FATAL:  database "db_error" does not exist
```

The solution is easy, create and migrate your database however new developers may not know these commands by memory. Instead of requiring the developer to search for a solution, tell them how to fix the problem in the error message:

```
ActiveRecord::NoDatabase: FATAL:  database "db_error" does not exist
Run `$ bin/rake db:create db:migrate` to create your database
```

Active Record should not know about `rake db:migrate` so this additional information needs to come from the railtie. Potential alternative implementation suggestions are welcome.
Merge pull request #13427 from schneems/schneems/cannot-connect-postgres-error

Tell how to Create a Database in Error Message
[ci skip] a destroy action in controller, not delete [getting_stated.md].
Do not store production information in .yml files

Instead, read information from environment variables.
Merge pull request #13462 from JuanitoFatas/getting-started

[ci skip] a destroy action in controller, not delete [getting_stated.md].