aufs3 and aufs4 GIT release (linux-v4.8)

[s***@users.sourceforge.net]

o bugfix
All are in userspace aufs-util.git and reported by OmegaPhil.
- simplify LibAuDir variable
- stop evaluating test_glibc when 'make clean'

o news
- linux-v4.8 is released and aufs4.8 too.
- linux-v4.6 is marked as EOL and aufs4.6 too.


J. R. Okajima

----------------------------------------
- aufs4-linux.git
none but new aufs4.8

- aufs4-standalone.git
ditto

- aufs-util.git
version aufs4.1
bugfix, simplify LibAuDir variable
bugfix, stop evaluating test_glibc when 'make clean'
tiny, silence a garbage
make sure all are built before installing