src: increase default semi space size to 64mb
An attempt at increasing the default semi-space as per the discussion here https://github.com/nodejs/performance/issues/67
(not sure if its testable)
Do not update/delete: Banner broadcast message test data
Do not update/delete: Notification broadcast message test data
An attempt at increasing the default semi-space as per the discussion here https://github.com/nodejs/performance/issues/67
(not sure if its testable)