* Added a 'LOGS.LOCK_USER_NAME' field to the database.
* Added a 'LOGS.LOCK_STATION_NAME' field to the database.
* Added a 'LOGS.LOCK_IPV4_ADDRESS' field to the database.
* Added a 'LOGS.LOCK_DATETIME' field to the database.
* Incremented the database version to 273.
* Added log locking logic to rdlogedit(1).
* Implemented application of the 'Purge Logs' setting when creating
logs manually.
* Changed the wording of the 'Purge Logs' and 'Purge ELR Data'
control in the Edit Service dialog in rdadmin(1).
* Added 'RDLog::create()' and 'RDLog::remove()' static methods.
* Modified the Edit Log screen in 'rdlogedit/edit_log.cpp' to
display the link Start Time and Length for Traffic and Music links
in the 'EXT DATA' column.
* Removed display of the link Length for Traffic and Music links
from the LENGTH column in 'rdlogedit/edit_log.cpp'.