Shrink file systems to exact size (#701075)

Ext[234] file systems were being shrunk 1 KiB too small.  Ntfs and
reiserfs file systems were being shrunk 1 byte too small.  The resultant
file systems were ending up 1 block smaller than they could have been.

This looks like an accidental leftover from when GParted use to:
1) Shrink the file system 1 cylinder too small
2) Shrink the partition
3) Grow the file system to fill the partition
Relevant commit:

    d663c3c2
    removed cylindersize buffering during resize from the filesystems

Closes Bug #701075 - Setting the backup boot sector when resizing NTFS