Ensure grep tests run to completion.
Run gcc tests in Chapter 6 as a non-privileged user.
Move shadow to before gcc so the gcc tests can
use su to run as a non-privileged user.
Add perl Configure options in Chapter 5 to ensure
no host system libraries are used.
Update minimum make version to 4.0 required by glibc-2.28.
Update bzip2 url to a new location.
Update to linux-4.17.14.
git-svn-id: http://svn.linuxfromscratch.org/LFS/trunk/BOOK@11446 4aa44e1e-78dd-0310-a6d2-fbcd4c07a689
