Update dependencies and atoum-edge

I updated everything, according to @stof comments: `@dev` is not required in root package. It is implicit when requiring `dev-*` packages.

I also updated atoum's edge branch:

* rebased against master
* merge extension API into it

**BUT**

* atoum test suite produces segfaults on PHP 5.6beta4
* I can't run the pickle test suite with your last patch as I get a fatal:

```
Fatal error: Call to undefined function ƒ() in /Users/julien.bianchi/repositories/jubianchi/pickle/pickle/vendor/hoa/realdom/Hoa/Realdom/Disjunction.php on line 563

Call Stack:
    0.0105    1884736   1. mageekguy\atoum\scripts\runner::mageekguy\atoum\scripts\{closure}() /Users/julien.bianchi/repositories/jubianchi/pickle/pickle/vendor/atoum/atoum/classes/scripts/runner.php:0
    0.0105    1885808   2. mageekguy\atoum\scripts\runner->run() /Users/julien.bianchi/repositories/jubianchi/pickle/pickle/vendor/atoum/atoum/classes/scripts/runner.php:537
    0.0153    2654448   3. mageekguy\atoum\script\configurable->run() /Users/julien.bianchi/repositories/jubianchi/pickle/pickle/vendor/atoum/atoum/classes/scripts/runner.php:204
    0.0202    2746056   4. mageekguy\atoum\script->run() /Users/julien.bianchi/repositories/jubianchi/pickle/pickle/vendor/atoum/atoum/classes/script/configurable.php:89
    0.0203    2755208   5. mageekguy\atoum\scripts\runner->doRun() /Users/julien.bianchi/repositories/jubianchi/pickle/pickle/vendor/atoum/atoum/classes/script.php:302
    0.0292    4151304   6. mageekguy\atoum\runner->run() /Users/julien.bianchi/repositories/jubianchi/pickle/pickle/vendor/atoum/atoum/classes/scripts/runner.php:1045
    0.1156    5383664   7. mageekguy\atoum\test->addExtensions() /Users/julien.bianchi/repositories/jubianchi/pickle/pickle/vendor/atoum/atoum/classes/runner.php:443
    0.1156    5383848   8. mageekguy\atoum\test->addExtension() /Users/julien.bianchi/repositories/jubianchi/pickle/pickle/vendor/atoum/atoum/classes/test.php:1770
    0.1156    5383968   9. Atoum\PraspelExtension\Manifest->setTest() /Users/julien.bianchi/repositories/jubianchi/pickle/pickle/vendor/atoum/atoum/classes/test.php:1756
    0.1156    5384448  10. Composer\Autoload\ClassLoader->loadClass() /Users/julien.bianchi/repositories/jubianchi/pickle/pickle/vendor/atoum/atoum/classes/test.php:0
    0.1156    5384616  11. Composer\Autoload\includeFile() /Users/julien.bianchi/repositories/jubianchi/pickle/pickle/vendor/composer/ClassLoader.php:270
    0.1162    5513904  12. include('/Users/julien.bianchi/repositories/jubianchi/pickle/pickle/vendor/hoa/realdom/Hoa/Realdom/Realdom.php') /Users/julien.bianchi/repositories/jubianchi/pickle/pickle/vendor/composer/ClassLoader.php:378
    0.1164    5520728  13. Hoa\Core\Consistency\Consistency->import() /Users/julien.bianchi/repositories/jubianchi/pickle/pickle/vendor/hoa/realdom/Hoa/Realdom/Realdom.php:59
    0.1164    5520816  14. Hoa\Core\Consistency\Consistency->_import() /Users/julien.bianchi/repositories/jubianchi/pickle/pickle/vendor/hoa/core/Hoa/Core/Consistency.php:168
    0.1164    5522640  15. spl_autoload_call() /Users/julien.bianchi/repositories/jubianchi/pickle/pickle/vendor/hoa/core/Hoa/Core/Consistency.php:288
    0.1164    5522680  16. Composer\Autoload\ClassLoader->loadClass() /Users/julien.bianchi/repositories/jubianchi/pickle/pickle/vendor/hoa/core/Hoa/Core/Consistency.php:288
    0.1164    5522856  17. Composer\Autoload\includeFile() /Users/julien.bianchi/repositories/jubianchi/pickle/pickle/vendor/composer/ClassLoader.php:270
    0.1167    5589944  18. include('/Users/julien.bianchi/repositories/jubianchi/pickle/pickle/vendor/hoa/realdom/Hoa/Realdom/Disjunction.php') /Users/julien.bianchi/repositories/jubianchi/pickle/pickle/vendor/composer/ClassLoader.php:378
```
it is not a rolling release. It is "no release". There is only the unstable version in this case