if celeryconfig doesn't exists add /usr/openquake as python search path
if celeryconfig doesn't exists add /usr/openquake as python search path


Former-commit-id: 0f095eedab3f30833700409db3b4a1bca3e50465 [formerly bfb4e852bb44151bb0b0fdcb51df77fa72849b2e]
Former-commit-id: 796e6c82440537a76b8e53f277c4499b5738732d
gem/oq-engine,gem/oq-engine,gem/oq-engine,gem/oq-engine,gem/oq-engine