Log Message:
Import unrar-5.9.4 as archivers/unrar5

unRAR is a utility to extract, test and view the contents of archives
created with the RAR archiver, version 1.50 and above.  The unRAR
utility is a minor part of the RAR archiver and contains RAR
uncompression algorithm. UnRAR requires very small volume of memory to
operate.

The license for this software states that "the code may not be used to
develop a RAR (WinRAR) compatible archiver."

This version exists for compatibility with legacy systems that lack a
C++11 compiler.