[MonologBridge] added integration with the console component
merged branch Tobion/monolog-console-integration (PR #8167)

This PR was squashed before being merged into the master branch (closes #8167).

Discussion
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[MonologBridge] added integration with the console component

This adds integration with the console component by adding ConsoleHandler and ConsoleFormatter which can be used to show log messages in the console output depending on the verbosity settings.
This PR splits the reusable classes from symfony/MonologBundle#42 into the bridge.
It has been reviewed by @Seldaek

| Q             | A
| ------------- | ---
| Bug fix?      | no
| New feature?  | yes
| BC breaks?    | no
| Deprecations? | no
| Tests pass?   | yes
| Fixed tickets | #8033
| License       | MIT
| Doc PR        | will be done when this is used by the MonologBundle

Commits
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c0b5996 [MonologBridge] added integration with the console component