* RemoveEntry(): set inode id to zero when reaching the end of block
* FindEntry(): keep on searching if Get() returns B_BAD_DATA
* added _Offset() based on fLogicalBlock and fDisplacement
* Next(): keep on searching when inode id is zero; also when entry length is zero, keep on with next block
* added GetNext() to get the next valid entry.
* Get(): now returns B_BAD_DATA on a zero length or inode id.
git-svn-id: file:///srv/svn/repos/haiku/haiku/trunk@39343 a95241bf-73f2-0310-859d-f6bbb57e9c96