Add a thread-quitting cleaning method. when a thread is quitting, its finished signal will be caugth,
so that , db resource class can clean the database connections belongs to this thread one by one.
this method is very important in some situation, such as Qt-concurrent threading, threads will be created, deleted frequently.
We re-complete the translation "QS" files , from ANSI to Chinese
Add a commandline auto start action, perpared for batch server forking.
Add a auto-join cluster method, as soon as the server node be started, a join-cluster approach will be taken.