TransactionalMap.putIfAbsent unlock

(cherry picked from commit 54760280e387a92f2767054007142fda4ae46ae0)
fix for remove, and replace, tests simplification

(cherry picked from commit 7d624d9beb907e439068c8c39a1d0fd2140da050)
Pulled out transaction unlock method. Improved tx map test method names.

(cherry picked from commit f1eaad7874e772f632b6ad144fce7b2c9cc4e485)
Merge pull request #3159 from mdogan/fix/3.3/port-pr-3092

Forward Port - TransactionalMap.putIfAbsent unlock