'RELENG_7_0_0_RELEASE'.

This commit was manufactured to restore the state of the 7.0-RELEASE image.

  * "compression_program" support uses an external program
  * Portability: no longer uses "struct stat" as a primary
    data interchange structure internally
  * Part of the above: refactor archive_entry to separate
    out copy_stat() and stat() functions
  * More complete tests for archive_entry
  * Finish archive_entry_clone()
  * Isolate major()/minor()/makedev() in archive_entry; remove
    these from everywhere else.
  * Bug fix: properly handle decompression look-ahead at end-of-data
  * Bug fixes to 'ar' support
  * Fix memory leak in ZIP reader
  * Portability: better timegm() emulation in iso9660 reader
  * New write_disk flags to suppress auto dir creation and not
    overwrite newer files (for future cpio front-end)
  * Simplify trailing-'/' fixup when writing tar and pax
  * Test enhancements:  fix various compiler warnings, improve
    portability, add lots of new tests.
  * Documentation: document new functions, first draft of
    libarchive_internals.3

MFC after: 14 days
Thanks to: Joerg Sonnenberger (compression_program)
Thanks to: Kai Wang (ar)
Thanks to: Colin Percival (many small fixes)
Thanks to: Many others who sent me various patches and problem reports.

  * libarchive_test program exercises many of the core features
  * Refactored old "read_extract" into new "archive_write_disk", which
    uses archive_write methods to put entries onto disk.  In particular,
    you can now use archive_write_disk to create objects on disk
    without having an archive available.
  * Pushed some security checks from bsdtar down into libarchive, where
    they can be better optimized.
  * Rearchitected the logic for creating objects on disk to reduce
    the number of system calls.  Several common cases now use a
    minimum number of system calls.
  * Virtualized some internal interfaces to provide a clearer separation
    of read and write handling and make it simpler to override key
    methods.
  * New "empty" format reader.
  * Corrected return types (this ABI breakage required the "2.0" version bump)
  * Many bug fixes.

a vanilla 2-clause BSD license, but somehow some confusing
extra verbage get copied from somewhere.

Also, update the copyright dates to 2007 for all of the files.

Prompted by: several questions about what those extra words really mean

"return", "ridiculous", and "success".

MFC after:	3 days

   * If write block size is zero, don't block at all.
     This supports the unusual requirement of applications
     that need "no-delay" writes.
   * Expose _write_finish_entry() to give such applications more
     control over write boundaries.  (Normal applications do not
     need this, as entries are completed automatically.)
   * Correct the type of write callbacks; this is a minor API
     change that does not affect the ABI.
   * Correct the error handling in _write_next_header() around
     completing the previous entry.
   * Correct the documentation for block-size markers:  Remove
     docs for the long-defunct _read_set_block_size(); document
     all of the write block size manipulators.

MFC after: 14 days

PR: bin/86742

archive_{read,write}_open_filename():
   * Update Makefile to build the files using the new name.
   * Update docs to document the new names, mentioning the
old ones as "deprecated synonyms."
   * The old filenames will be reconnected to the build soon;
I'll soon recyce those files for a slightly different purpose.