This reverts commit 7ad461b4.

This way we don't define all the validation methods for all associations by
default, but only when needed.

[#3355 state:resolved]

[#3467 state:resolved]
Signed-off-by: NEloy Duran <eloy.de.enige@gmail.com>

[#3468 state:resolved]
Signed-off-by: NEloy Duran <eloy.de.enige@gmail.com>

When rendering layouts with blocks, use #capture to avoid assuming that the return value is the block's content.
Signed-off-by: NYehuda Katz <wycats@Yehuda-Katz.local>

Update AC::Middleware to play better with the normal AC::Metal stack. This required stopping to use #call for non-rack-related stuff

Signed-off-by: NMichael Koziarski <michael@koziarski.com>

Replace explicit for-loops by faster enumeration methods.

[#3158 state:committed]