Improve the client-install. You can now do a "make client-install" from

the top level.  This will build all the necessary binaries and then install
them.  This works on FBSD4 and RHL7.3.  It still doesn't work on FBSD5
(newer compiler that no longer supports a style of use of _FUNCTION_ in the
event lib) or RHL9 (event lib needs SSL lib which has a bad dependency
on Kerberos).  Notes:

- requires that elvin libraries be installed on nodes (they are) to build
  event agents, requires linuxthreads be installed on FBSD (it is now) to
  build imagezip (which is installed, but is not strictly necessary)

- installed event-agents and other binaries are stripped

- added a few missing files to the source tree for bsd (healthd.conf)
  and linux (healthd.conf, rc.local)

- the only thing that doesn't get rebuilt in /usr/local/etc/emulab is
  healthd, I couldn't quickly find how it gets built

- uses a scaled down version of libtb with no DB functions (since mysql
  isn't installed on nodes).  N.B. DO NOT DO A CLIENT INSTALL FROM YOUR
  REGULAR OBJ TREE OR ELSE YOU MAY WIND UP WITH A NEUTERED VERSION OF
  libtb.a!

The build-as-well-as-install semantics are counter to the regular install
targets, but this is what we gotta do for now.  Once the TB source builds
under Linux and newer BSDs, we could undo this and just require that people
do a regular "make" followed by "make client-install"  OTOH, there should
be no reason to require installation of mysql and other server-side packages
just to build clients (or make them sit through the compilation of assign),
so maybe we will keep the client build special.