avoid double logging by sending output of root logger to /dev/null

self.tk doesn't exist

fix BLACS and ScaLAPACK build

fix logging issues + cleanup

fix BLACS and ScaLAPACK build: introduce gompi toolkit so that OpenMPI is a direct toolkit dependency, and adjust ATLAS, BLACS, FFTW, LAPACK, ScaLAPACK and goalf toolkit easyconfigs accordingly