drop db_prepare_date - it's not database api's 'job' to check that dates are not >2100 etc. Additionally this function ignores adodb's date handling.
add db_bind_date and db_bind_timestamp.
fix timetracking stats to work with the above changes.

git-svn-id: http://mantisbt.svn.sourceforge.net/svnroot/mantisbt/trunk@5001 <a class="text" href="/?p=mantisbt.git;a=object;h=f5dc347c">f5dc347c</a>-c33d-0410-90a0-b07cc1902cb9