- Added a test for ftruncate() to configure. If the function does not

- Added a test for ftruncate() to configure.  If the function does not
  exist, we disable support for --inplace.
- Mention the availability of inplace support in the --version output.
- Improved the sorting of the targets to include sub-sorting the same
  target by sum1, sum2, and offset.  This makes the comparisons later
  when searching for matching targets more optimal.
- We now mark chunks that were at idential offsets so that we can
  potentially reuse them.
- Prefer a cunk with an identical offset over another matching chunk.
- Fixed a bug in one error message that was outputting fnametmp instead
  of fnamecmp.
- Don't call cleanup_set() for an inplace transfer.