New feature: External C/C++ dependencies can be bundled up for easy
redistribution.
In this first stage of implementing this feature for the UNIX build,
the dependencies are not installed by default when making an
installation or a release. Instead, there is a separate target named
'install-deps' that must be run to install dependencies. By default,
dependencies install into the same directory tree as VR Juggler, but
this can be changed by setting the variable deps_prefx on the command
line when running GNU make.
For the developer installation (the instlinks stuff), the dependecies
are installed into the instlinks tree. Since the *-config scripts have
not yet been updated, the only real effect of this is that developers
can set $LD_LIBRARY_PATH to point only to $VJ_BASE_DIR/lib and get all
the shared libraries resolved. The updates to the *-config scripts are
the next stage.
