Allow everything to be built from the top level directory with just
'make', cleaned with 'make clean', and installed with 'make
install'. Also support these in any particular subdirectory.
Specifying 'make VERBOSE=1' will print each ld/g++/etc. command as
it runs.
Kernel and early host tools (IPCCompiler, etc.) are built as
object.host.o so that they don't conflict with other things built
with the cross-compiler.
Instead of implementing menu applets as their own thing, they are now
WSWindows of WSWindowType::MenuApplet.
This makes it much easier to work with them on the client side, since
you can just create a GWindow with the right type and you're in the
menubar doing applet stuff :^)
