Added PrintF output whenever a zone is created or destroyed. Also
enables setting of a name for each zone, which can then be shown
in the v8-heap-stats tool: https://github.com/mlippautz/v8-heap-stats/pull/2

BUG=v8:5489

Review-Url: https://codereview.chromium.org/2397573007
Cr-Commit-Position: refs/heads/master@{#40168}