0.17 release
Use /host_targets/ on the host and /srv/mer/targets on the VM
Add --devel support in sdk-manage to allow webapp to handle
header packages better
Ensure target is synchronised after --devel zypper operations.
Improve Scratchbox2 setup and fix cross-486 support
Add ttl mount option from rbraakman

Signed-off-by: David Greaves <david@dgreaves.com>