chore, import latest GNUmakefile that names the dist version correctly
chore, PEBKAC, now that pkg-config's gone AC_SUBST octave_CFLAGS and octave_LIBS ourselves
chore, actually mimic pkg-config by AC_ARG_VARing octave_{CFLAGS,LIBS}
minor, don't use hardcoded octave path, substitute ${libdir}
fix, PEBKAC, name directories without trailing slash
Merge branch 'bld/dist'

* bld/dist:
  fix, PEBKAC, name directories without trailing slash
  minor, don't use hardcoded octave path, substitute ${libdir}
  chore, actually mimic pkg-config by AC_ARG_VARing octave_{CFLAGS,LIBS}
  chore, PEBKAC, now that pkg-config's gone AC_SUBST octave_CFLAGS and octave_LIBS ourselves
  chore, import latest GNUmakefile that names the dist version correctly