Refactor TraceParamsImpl and company

git-svn-id: svn+ssh://svn.code.sf.net/p/firebird/code/firebird/trunk@59235 65644016-39b1-43b1-bf79-96bc8fe82c15
Fixed problem with hash join using keys with non-none character set. Dmitry, please review.

git-svn-id: svn+ssh://svn.code.sf.net/p/firebird/code/firebird/trunk@59236 65644016-39b1-43b1-bf79-96bc8fe82c15
Misc.

git-svn-id: svn+ssh://svn.code.sf.net/p/firebird/code/firebird/trunk@59237 65644016-39b1-43b1-bf79-96bc8fe82c15