(1) {emulators,wip}/simulavr now packages fine.
    Follow (sync) how-it-has-good shape. (Makefile)
    -- meaning that not to have
    -#.include "../../wip/avr-libc/buildlink3.mk"
    but
    +BUILD_DEPENDS+=                avr-libc-[0-9]*:../../wip/avr-libc
(2) Sort Makefile as similar as doc/Makefile-example
(3) Add one item on TODO
    automake-1.14 has a problem to package, while 1.11 was OK.
      config.status: creating Makefile
      config.status: error: cannot find input file: `src/Makefile.in'