Import libarchive-3.1.2.

-Add basic archive read and write filter support for lrzip.
-Implement function used to seek within data blocks.
-Add support for lzop.
-Introduce uuencode filter.
-Introduce b64encode filter.
-Add support for grzip compression.
-Add support for writing v7 tar format.
-Implement functions to manually set the format and filters used.
patch(1): When -C is specified, do not claim to have saved rejects.

Submitted-by:  Loganaden Velvindron
Dragonfly-bug: <http://bugs.dragonflybsd.org/issues/2359>
patch(1): Fix typo.
Merge branch 'vendor/LIBARCHIVE'
Adjust files for libarchive-3.1.2 import.