nightly update

git-svn-id: svn+ssh://svn.code.sf.net/p/firebird/code/firebird/trunk@57831 65644016-39b1-43b1-bf79-96bc8fe82c15
recent version of autoconf/automake/libtool  complain about the firebird
scripts aclocal: warning: autoconf input should be named 'configure.ac', not
'configure.in'


git-svn-id: svn+ssh://svn.code.sf.net/p/firebird/code/firebird/trunk@57835 65644016-39b1-43b1-bf79-96bc8fe82c15
Work in progress standardizing the external engines API.

git-svn-id: svn+ssh://svn.code.sf.net/p/firebird/code/firebird/trunk@57836 65644016-39b1-43b1-bf79-96bc8fe82c15
Work in progress standardizing the external engines API.

git-svn-id: svn+ssh://svn.code.sf.net/p/firebird/code/firebird/trunk@57837 65644016-39b1-43b1-bf79-96bc8fe82c15