IQA-463: LLError::addRecorder() claims ownership of passed Recorder*.

That is, when the underlying LLError::Settings object is destroyed -- possibly
at termination, possibly on LLError::restoreSettings() -- the passed Recorder*
is deleted.
There was much existing code that seemed as unaware of this alarming fact as I
was myself. Passing to addRecorder() a pointer to a stack object, or to a
member of some other object, is just Bad. It might be preferable to make
addRecorder() accept std::auto_ptr<Recorder> to make the ownership transfer
more explicit -- or even boost::shared_ptr<Recorder> instead, which would
allow the caller to either forget or retain the passed Recorder.
This preliminary pass retains the Recorder* dumb pointer API, but documents
the ownership issue, and eliminates known instances of passing pointers to
anything but a standalone heap Recorder subclass object.