tools/build/CMake/testing/* contains a projects a,b,c,d,e arranged
like this:
A
/ \
B C
\ /
D E
for checking propagation of usage requirements, dependency calculation, etc.
basic "usage requirements" works thought the full diamond above isn't
fully peppered with asserts yet. You can set the following "properties"
on libs:
COMPILE_FLAGS
STICKY_COMPILE_FLAGS
SHARED_COMPILE_FLAGS
STICKY_SHARED_COMPILE_FLAGS
STATIC_COMPILE_FLAGS
STICKY_STATIC_COMPILE_FLAGS
The thinking is that toolset and threading will be "one scope up",
that this level can remain ignorant.
there's a variable RUN_SELFTESTS in boost.cmake that turns
off building of boost and turns on building of the
testing stuff.
