Automatic merge from branch-5.4

* origin/branch-5.4:
  Refactor a bit ComponentContainer
  stabilize ProjectDrilldownTest
  SONAR-7125 use efficient delete dir code in core, batch and server
  SONAR-7125 use efficient delete dir from NIO in sonar-api
  SONAR-7125 add FileUtils in sonar-core with efficient delete methods
  SONAR-7125 use efficient delete dir method in sonar-process
  SONAR-7125 use nio to clean temp directory at startup