Remove Errors module
Make legacy exceptions part of the Symfony HttpKernel for cross compatibility.
Update documentation on events

  - corrections to method calls
  - event names no longer necessary due to Symfony
Remove prehistoric module support.
Patch in request hack.

This is an interim way to handle request scope which the old Zikula doesn't have.
It makes it a lot easier to patch in the kernel workflow this way.
BC handling for throwing a redirect exception. From now on, we return a RedirectResponse
First attempt at switching to HttpKernel workflow
Remove _controller from legacy routing. We dont use this and it conflicts with Symfony's RouterListener
Modify RouteListener not to throw a RouteNotFound exception so the next
router can be called.
Update changelog
Correct typos and comments
Remove unused code and add condition to theme-exceptions
Update changelog
Merge pull request #1264 from zikula/kernel_switch

Switch to HttpKernel