Set require-dev as suggest feature , because require-dev has not recursive

Add suggest explication
Format code. #mania
Uncaught exceptions always print previous ones.
Add Hoa\Core\Exception\Group.

A Hoa\Core\Exception\Group instance is an exception that contains a
group of exceptions.
Fix a typo. Thanks @CircleCode!
Allow to call getValidCallback() without argument.
Hoa\Core\Exception\Group supports transactions.

Example:
    $e   = new Hoa\Core\Exception\Group('This is a cluster', 7);
    $e1  = new Hoa\Core\Exception('Test %d', 1, 41);
    $e2  = new Hoa\Core\Exception('Test %d', 2, 42);
    $e3  = new Hoa\Core\Exception('Test %d', 3, 43);
    $e4  = new Hoa\Core\Exception('Test %d', 4, 44);
    $e[] = $e1;

    $e->beginTransaction();
    $e[] = $e2;
    $e[] = $e4;
    $e->cancelTransaction();

    var_dump(count($e)); // int(1)
Format spaces when raising a group of exceptions.
Use traditionnal transaction vocabulary.
The $_SERVER['LANG'] is not always defined.
Update exit message.
Update API documentation.
Bypass parser to exit when Hoa is included twice.

Hoa\Core has a special constant HOA to detect whether the core is
included twice. Unfortunatly, the parser failed with the function ƒ
before executing the code. We move the ƒ function into
Hoa\Core\Consistency to fix this.

Example:
    require '/usr/local/lib/Hoa/Core/Core.php';
    require '/usr/local/lib/Hoa/Core/Core.php';

Before:
    PHP Fatal error:  Cannot redeclare ƒ() (previously declared in…
    Fatal error: Cannot redeclare ƒ() (previously declared in…

After:
    Hoa main file (Core.php) must be included once.
Remove internal debugger.
Add the Hoa\Core::uuid() static method.

Moved from `hoa core:uuid`.
Add the Hoa\Core::getPHPBinary() static method.
Initialize mbstring directly.
import() wildcard * supports Composer.
Fix a bug with import + * + Composer.
Fix a bug with import + * + Composer.

Thanks @stephpy!