add onDestroy callback method to LifecycleCallback interface which is invoked during servlet container shutdown
create destroyProcessors method
create Destroyable interface and implement this interface for all processors using ObjectPoolHelper
log with debug level when objectHelper is destroyed
add more logging with debug level
add unit test
prefer using WroConfigurationFactory to configure WroConfiguration in WroFilter
create PropertiesFactory interface to make it possible to reuse in ConfigurableWroManagerFactory configurations used by WroConfiguration factory
Destroy operation should be invoked also on decorated processors.
managerFactory should not fail when destroying uninitialized factory
create marker interface which extends all interfaces a processor can implement
Merge branch '1.7.x' into issue745
Merge branch 'issue745' into 1.7.x