[zen-56][zendframework/zf2#1550] pull from peering managers first
[zen-56][zendframework/zf2#1550] pull from peering managers first

- Necessary to allow overriding a plugin; reported by Evan Coury

weierophinney/zend-servicemanager,akrabat/zend-servicemanager,MadCat34/zend-servicemanager,matwright/zend-servicemanager,prolic/zend-servicemanager