Merge branch 'maint'

* maint:
  Fall back to preprocessor mode when seeing a non-regular include file
  Properly close fd in manifest_get if gzdopen fails
  Check for CRC errors after decompression
  doc: Sort environment variables correctly
  Minor doc string fixes
  Fix NFS object corruption

diff --cc ccache.c
Simple merge

diff --cc manifest.c
Simple merge

diff --cc util.c
Simple merge