Removed need for llGetAttached()

If RLVok is true.... then the Key is attached. Removing this
spurious test makes RLV operations faster.
wearLock was never set; fixed.

wearLock variable was never set via Link Messages; this has been
fixed.
llGetAttached replaced with cdAttached, etc

isAttached (int) was added and used, and llGetAttached was
replaced almost entirely by cdAttached. The use of llGetAttached()
everywhere may not have been as much an irrelevance as once appeared.
Removed old Link Message 850

Without database backend this link message is no longer relevant.
Minor documentation added

More code clarity and documentation added.
Updated document dates; added debug in StatusRLV

If RLVok is false, then should not be sending messages to
StatusRLV .... also updated header Dates of all files.