Fix for [JENKINS-18950] issue (reports => running out of memory).

Fixed problem of running out of memory under heavy use like ours:
- reports not kept in memory anymore but made on demand;
- logging changes due to unserializable listener-logger.
Fix for [JENKINS-18950] issue (reports => running out of memory).
Fix for [JENKINS-18950] issue (reports => running out of memory).
Merge branch 'reports' of github.com:Adynatos/valgrind-plugin into review
fixed code formatting for consistency
organized imports
suppress deprecation warning