Warmup

This will do a warmup base on the map file if the dump-autoload --optimize have been in composer. A method is also available to pass a array of files if needed.

The unit test have been started but are not really efficient since we should check if the proper file have been generated. But since I do not no how to reproduce the All the container configuration in a test environment it's pretty hard to do...

I've try to modify the minimum the actual class, so just one method to access the initial Autoloader have been add to existing class.

In my project I have more than 4k classe to generate, this can take a lot of time and up to 2G of memory (I didn't look for where memory is kept in the system...)