Fixed 0007030: Port: installtion fails - administrator have no rights on db.
Fiixed 0007031: Port: is_writable never success in install.php.

git-svn-id: http://mantisbt.svn.sourceforge.net/svnroot/mantisbt/branches/BRANCH_1_0_0@4078 <a class="text" href="/?p=mantisbt.git;a=object;h=f5dc347c">f5dc347c</a>-c33d-0410-90a0-b07cc1902cb9