Removed useless test in misc/cron/archive.php

In the past, `misc/cron/archive.php` used to be included in the console command `core:archive`. But not anymore, so this test can be removed.
The console now includes the optional file bootstrap.php

Users can add a custom `bootstrap.php` file at the root of Piwik to customize constants. This file is included (if exists) in `index.php` and `piwik.php` but not in the console. This is now fixed.

See the user docs about this: http://piwik.org/docs/include-piwik-in-your-project/
Moved common bootstrap code in a `core/bootstrap.php` file

This file is not in a class because it needs to be compatible with PHP 4.
Removed Piwik\Loader: Composer's autoloader is now included in core/bootstrap.php
Added a comment
refs #6753 uncommenting tests to see whether they fail. Cannot execute them directly as I am using PHP 5.3
refs #6753 the processed data seems to be ok when comparing them with daily and monthly expected
DI config: renamed the `old_config` prefix to `ini`

Initially we considered dropping the `ini` config, but the current stance is we keep `config.ini.php` because it's a user friendly config.
fix markdown formatting for test readme (code blocks require 4 spaces, not tabs)
fix spelling in testing readme
Merge pull request #6903 from FelixSchwarz/testing-readme-fixes

Trivial fixes in tests README
Unset logger instance in Fixture tear down.
#6881 Disable logging in 'climulti:request'

The `climulti:request` commands now run in "quiet" mode so it will not log to the output.
Merge pull request #6891 from piwik/bootstrap

Simplified bootstrap files
Merge pull request #6893 from piwik/6753

Enabled some ArchiveCronTests
Merge pull request #6894 from piwik/ini-config

DI config: renamed the `old_config` prefix to `ini`
fixes #6831 only include file once
Adding monolog mention in changelog
2.10.0-rc2
Use latest doctrine/cache including file cache edge cases fixes. Add the alias repo to piwik composer.json so composer update will fetch this code.