Worker info:

Add timers to ttrack worker info:
 - createDate (when the worker process started)
 - registerDate (when the registration occured)
 - puliversion (a string indicating the puli version number)
Merge branch 'hotfix/update_stats_at_command_end' into develop
Add type testing in update Stats
Minor update for pul_rn and pul_query

- add doc to pul_rn and pul_query
- user can sort result of pul_query
Merge branch 'hotfix/restart_part_of_graph_with_dependencies' into develop
Print version number on boot
Add stats mecanism

- stats can be activated in config
- logs data in separate stats.log file
- data
  - timers for the main loop
  - count of request (by type)
  - count of several business processes (add graph, update comandetc)
Change version number
Merge branch 'release/1.6.5'