fixed EXT-5456 Messages from objects are shownas messages from Second Life in nearby chat history from the prev session

Completed things which were agreed on:
- system messages in the log file are prepended with "Second Life:" after the timestamp
- object names set which are parsed extended to object names consisting with any number of words

Side effect:
"Second Life:" is shown as From Name in Nearby Chat when in plain text chat

--HG--
branch : product-engine