Merge: r269884

Complete the usr.bin/yacc kyua integration work I originally
submitted via r268811

• Install the Kyuafile by adding FILES to FILESGROUPS
• Run the testcases with an unprivileged user
  
  Some of the testcases depend upon behavior that's broken when run as root on FreeBSD because of how permissions are treated with access(2) vs eaccess(2), open(2), etc

• Simplify the test driver to just inspect the exit code from run_test because it now exits with 0 if successful and exits with !0 if unsuccessful
• Don't do ad hoc temporary directory creation/deletion; let Kyua handle that
• Add entries for files removed in r268811 to OptionalObsoleteFiles.inc

PR: 191020
X-MFC with: r268811
Approved by: jmmv (mentor)
Reviewed by: bapt
Sponsored by: EMC / Isilon Storage Division