ZF-11295: no information about subcontroller support

Description

i think the manual should have information about zf's support to subcontrollers.

many people like me get frustated for seeing no submodule support but the implemented approach besides being subtly different is not documented in the official manual.

Comments

I could not agree more as this is the first time when I hear about subcontrollers. Google tells very little about these, so it would be nice to get those documented. The best catch was this post.

edit: more on [https://github.com/adamlundrigan/…]

Closing as duplicate of ZF-3590. Issue will be fixed there.