Makefiles subsystem - Riccardo Facchetti - 15 Dec 00

The new Makefiles subsystem is designed to optimize the local
Makefile with global Rules and Targets.
There are two general Makefile fragments that are included during
generation of Makefile from Makefile.in. All Makefiles must include
these two general fragments that furnish general variables and general
target rules. Inclusion is done with the keywords @RULES@ and @TARGETS@
in the Makefile.in.
If you need to write a new Makefile, please look at an existing Makefile
for general information on how to organize the Makefile.
The fragments are in scripts/Rules.mak.in and scripts/Targets.mak
For a complete understanding of the inner working, please look at these
two fragments and at the Makefiles.

There are several local variables to the Makefiles used by fragments.
These variables are:

subdirs		subdirectories that contain a Makefile.in
allexe		contains all the binaries generated locally (libs and exes)
LOCALDEFS	local defines: -Dsomething

Targets needed by each local Makefile:

all-targets	is the list of all the local targets.