* 3.4:
[DI] Turn services and aliases private by default, with BC layer
[WebProfiler] Fix z-index for pinned AJAX block
Require v3.4+ of the var-dumper component
* 3.4:
Do not display short exception trace for built-in console exceptions
Deprecated the web_profiler.position option
[DI] rename ResolveDefinitionTemplatesPass to ResolveChildDefinitionsPass
Throw a meaningful exception when an undefined user provider is used inside a firewall
[DI] Allow processing env vars