💥✨ boot kernel depending on context

[QWp6t]

Overview

This PR changes how Acorn boots.

It more closely mirrors Laravel's boot process but applies a bit of logic to determine which Kernel to use.

💥 BREAKING CHANGES

The following contain breaking changes:

• Bootloader class
• bootloader function

All WordPress filters have been removed from the Bootloader.

This means that acorn/bootstrap, acorn/paths, acorn/paths.{path}, and acorn/ready have been removed.

This was done to limit unpredictable behavior. Since Acorn can boot much earlier, including instantly booting from a mu-plugin, then whether a filter is applied depends on the load order of plugins (or themes) that may try to use them.

A companion PR will be required in Sage's functions.php

-\Roots\bootloader();
+\Roots\bootloader()->boot();

closes #162