Merge branch 'jk/daemon-interpolate' into maint

The "interpolated-path" option of "git daemon" inserted any string
client declared on the "host=" capability request without checking.
Sanitize and limit %H and %CH to a saner and a valid DNS name.

* jk/daemon-interpolate:
daemon: sanitize incoming virtual hostname
t5570: test git-daemon's --interpolated-path option
git_connect: let user override virtual-host we send to daemon

diff --cc connect.c
Simple merge

diff --cc daemon.c
Simple merge