Fix entityvalidate property condition

Squashed commit of the following:

commit e351884bbba0f8797d7b5811e1efca2f93c39373
Author: Snir <snir@gizra.com>
Date:   Mon Sep 1 14:18:22 2014 +0300

    Fix condition.

commit d48cf4274d135565f0e8ae2df778716285d6d1b5
Author: Snir <snir@gizra.com>
Date:   Mon Sep 1 13:49:18 2014 +0300
Allow "X-HTTP-Method-Override" in request.

Client may send a POST request, but override the method to newer methods (e.g. PATCH, PUT).
Merge pull request #138 from Gizra/137

Allow "X-HTTP-Method-Override" in request.

Client may send a POST request, but override the method to newer methods (e.g. PATCH, PUT).
Add \RestfulInterface::publicFieldsInfo() for declaring fields.

Use \RestfulInterface::getPublicFields() to get the processed fields (i.e. with default values initiazlied).
Merge pull request #135 from Gizra/public-fields

Add \RestfulInterface::publicFieldsInfo() for users to declare their fields.

Also rename 'process_callback' to 'process_callbacks' and allow it to pass the value to multiple callbacks.
Merge 7.x-1.x