add example easyconfigs for libxcb and xcb-proto (although they're not used as dependencies anymore)

fix Meep build by using EBROOT instead of SOFTROOT, don't specify MKL for BLAS/LAPACK with goalf build

compile libmatheval with -fPIC, to fix broken libmatheval goalf build (flex libs are built with -fPIC)

move application log instead of creating a new handler per app (which doesn't track other EasyBuild modules log messages)