v1.3.22: threads marked as not keeping lisp alive

Threads started by AllegroServe to process requests are
marked as non-interactive threads so that they will not
prevent lisp from exiting.  Webaction's session reaper thread
is similarly marked.

Are there user visible changes in this commit?  yes/no

Is bootstrapping needed?   no

Are tests included for new features?  no new features

Tests run:  aserve test suite

Change-Id: I9a0cca59e14b92c5ac2c0bcfeac9e5162bcd8ba8