change version of goolf v1.6.5 to goolf v1.5.14, to align with existing gompi 1.5.12 easyconfig

@pescobar: as discussed

It makes a lot of sense since we already have a `gompi` 1.5.12 (no `goolf` though) that combines GCC 4.8.1 with OpenMPI 1.6.5...