[Security] Add SimpleForm authentication
[Security] Add simple_token auth method
[Security] Renamed simple_token to simple_http, added support for failure and success handler to both simple firewalls
fixed wrong Logger interface
moved the simple HTTP authenticator to a pre-auth one
[Security] allowed simple pre-auth to be optional if another auth mechanism already authenticated the user
marked some classes as being experimental in 2.3
[HttpFoundation][NamespacedAttributeBag] Refactoring of resolveKey() method
removed CHANGELOG for 2.0 as it is not maintained anymore
changed all version deps to accepts all upcoming Symfony versions
[Console] Added status code to CommandTester and ApplicationTester

Theses classes are already statefull. They contain the input and the
output data. So we can safely add the last status code to the class.
removed versions in composer.json files
[ADD] Component_Console -add suggest in the composer.json to event-dispatcher
merged branch fabpot/dep-versions (PR #8017)

This PR was merged into the master branch.

Discussion
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changed all version deps to accept all upcoming Symfony versions

Everything is in the title.

Commits
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b1c9fd2 removed versions in composer.json files
f41ac06 changed all version deps to accepts all upcoming Symfony versions
[Console] Removed the descriptor from data set providers.
[Console] fix test for NullOutput that does not print anything and add a failing test for verbosity
[Console] fix NullOutput

It should not extend from abstract Output class because than it inherits the useless constructor arguments and applies formatting in write() needlessly.
[Console] the default type value should use the constant in OutputInterface::write
[Console] fix abstract Output class that fasly claims to support guessing of decorated variable.

Also we don't need to typecast to boolean as its already done by the formatter and its his responsibility
[Console] fix phpdoc of Output classes (esp. regarding the new verbosities)

also add missing information