Updated http_cache/* articles to Symfony 4

[javiereguiluz]

I have a question about the old AppCache class. I've moved to src/AppCache.php under App namespace. Is that correct? And also: should we rename it to Cache or KernelCache or something else? AppCache was great when we had AppKernel ... but now we have just Kernel.

[weaverryan]

Hmmmm.

Two things:

1. One big difference is that, in Flex, you will need to create the "cache" kernel file, because you do not have it by default (like in the SE). @javiereguiluz have you made changes to the docs to reflect this? I admittedly only did a quick scan, but I didn't see it. It's out-of-scope, but perhaps we need a make: command to create this for you (and at least suggest the changes you also need in index.php).

2. What to call this class? I think CacheKernel - it's your kernel, but a Cache version if it :).

[weaverryan]

Status: Needs work

[weaverryan]

Thanks!