[ANN] INPATH is dead

good news, everyone!

the following commit just landed on master and removes the "wntmsc*" /
"unx*" directories below instdir and workdir.

you should do a "make clean" once after pulling it because all the build
output now goes into a different directory than before so you're
building from scratch anyway (and without make clean the old build
output will just waste storage space).

    commit b8002169336b6b7597d32755e41fa3dc2688539e

    remove INPATH and PROEXT

    - WORKDIR path is just workdir
    - INSTDIR path is just instdir
    - WORKDIR_FOR_BUILD is workdir_for_build
    - INSTDIR_FOR_BUILD is instdir_for_build
    - replace other usage of INPATH by combination of OS and CPUNAME

... and in case anybody was crazy enough to build multiple platforms
from the same source dir: please do an out-of-tree build (build dir
different from source dir), which is much more flexible and powerful
anyway since you can even build different configurations of the same
platform.