Minor edits to whats-new for v3.6
Minor edits to whats-new for v3.6

Former-commit-id: e1436150a0f1520dbad1bb22fdbec0c21d0b7a09 [formerly e1436150a0f1520dbad1bb22fdbec0c21d0b7a09 [formerly db67a7c0c17480f411cbbc09edd4edebf30a5253]]
Former-commit-id: 1934d085d77f4b5c68019c6ab90e1eccd041373e
Former-commit-id: d0031b2dc900a1f2c5936ca58708c56e3c55b338
gem/oq-engine,gem/oq-engine,gem/oq-engine,gem/oq-engine,gem/oq-engine