Fixed CORE-4555 - DDL trigger remains active after dropped.

git-svn-id: svn+ssh://svn.code.sf.net/p/firebird/code/firebird/trunk@60049 65644016-39b1-43b1-bf79-96bc8fe82c15
Implement improvement CORE-4556 : Allocate data pages in group of sequential ordered pages (extents)
Validation code will follow

git-svn-id: svn+ssh://svn.code.sf.net/p/firebird/code/firebird/trunk@60050 65644016-39b1-43b1-bf79-96bc8fe82c15