OAK-521 : Configurable AuthorizableAction(s)
- simplify actions
- add composite action provider
- make default impl a service
- fix configuration of access control action
- remove implementation specific action api from generic user configuration and make it a parameter of the user configuration parameters

OAK-522 : Pluggable User Management (wip)
- make configuration impl a service

OAK-754 : Pluggable Security Setup (wip)
- rename ConfigurationParameters#getNullableConfigValue and allow to specify a target class and fix usages
- ConfigurationParameters: improve convertion
- ConfigurationParameters: add more utility methods to create config params

git-svn-id: https://svn.apache.org/repos/asf/jackrabbit/oak/trunk@1521892 13f79535-47bb-0310-9956-ffa450edef68
OAK-754 	: Pluggable Security Setup  (wip)

git-svn-id: https://svn.apache.org/repos/asf/jackrabbit/oak/trunk@1521893 13f79535-47bb-0310-9956-ffa450edef68