Mark the masterfile-format type 'map' as deprecated
The map masterfile-format is very fragile and it needs API bump every time a RBTDB data structures changes. Also while testing it, we found out that files larger than 2GB weren't loading and nobody noticed, and loading many map files were also failing (subject to kernel limits).
Thus we are marking the masterfile-format type 'map' as deprecated and to be removed in the next stable BIND 9 release.
Closes #2882 (closed)