This version builds every module into the flua binary itself, since all
of the bootstrap tools are built -DNO_SHARED. As a result, we also
cannot dlsym(), so we can't really discover the names of our newly
builtin modules. Instead, just build out a linker set with all of our
luaopen_*() functions to register everything up-front.

Building in all of the modules isn't strictly necessary, but it means
that we have an example of how to add a bootstrap module everywhere you
go and one doesn't need to consider whether bootstrap flua can use a
module when writing scripts. On my build machine, the consequence on
our binary size is an increase from around 1.6M -> 1.9M, which isn't
really that bad.

.lua modules can install into their usual path below $WORLDTMP/legacy
and we'll pick them up automagically by way of the ctor that sets up
LUA_PATH early on.