Consider breaking the IoC and AOP docs out into a separate guide

[mikehearn]

The Micronaut Core user manual is one giant HTML page. A significant fraction of that is spent explaining the many features of the very impressive dependency injector and AOP framework, however this is overwhelming for new users who:

1. Likely don't care about features like defining custom bean scopes or their own advice.
2. Are presumably expecting to be instructed early in how the meat-and-potatoes stuff works, like how to define an HTTP server.

It would be good to spin these parts of the docs out into a separate guide like how Micronaut Views is done, with a small stub left behind that explains briefly what IoC and AOP are along with the sort of things you can do with the framework and enough introductory material to understand the rest of the user guide.