to use usleep on freeBSD/kFreeBSD systems we need to include unistd.h
Merge pull request #357 from matekm/usleep_bsd_fix

Fix compilation error on FreeBSD/kFreeBSD systems (missing include unistd.g for usleep)
few fixes for Hurd platform
Add log2 patches from ports needed to compile on FreeBSD < 8.3
Merge pull request #358 from matekm/gnu_hurd_fix

Fix compilation issues on GNU/Hurd platform
Fix some mangled text and bad formatted in ImageOutput docs
Update PDF docs
clang 3.1 warning elimination, found some legit bugs in DPX and Cineon
clang warning fixes
Filesystem changes to handle UTF-8 file paths on Windows.
* New Filesystem utility functions wrap fopen, open, and last_write_time
  but do so in a way that is safe for UTF-8 filenames on Windows (for example,
  we need to call _wfopen rather than fopen on Windows).
* The various plugins that called fopen/etc directly have been changed to
  use these Filesystems wrappers.
* Add Filesystem::convert_native_arguments which modifies an argv[] in
  place to convert Windows native to UTF-8 (does nothing for non-Windows).
* Create a wrapper for last_write_time that, like many other Filesystem
  wrappers, catches the exceptions that can happen
* Fix file handle leak with failed read of tiff/z gzipped files.
Revert recent change with TIFFdOpen -- it breaks subimage appending.
TypeDesc::equivalent() tests for type equality but allows triples with different vector semantics to match
Fix tiff issue with UTF-8 file paths, now using TIFFOpenW on Windows instead of
passing the file descriptor. This moves platform specific code into the tiff
plugin code, but it should be safer than trying to obtain the right file handle
with fopen.
Build cleanups and clang fixes (especially for Linux)
Extend ImageBuf to "wrap" an application buffer rather than own the memory.
ImageBuf: make copy_pixels fully 3D; add copy_from private method.
Implement ImageBuf::copy(), eliminate operator=
ImageBuf: add reres(), copy_metadata(), copy_pixels(); rename old copy_pixels to get_pixels.
Merge pull request #355 from lgritz/lg-imagebuf

Review: ImageBuf copy/assign refactor, app buffers
Typos left from last merge of ImageBuf refactor.  Oops.