Merge pull request #452 from wallyworld/remove-lock-dirs

Make local provider bootstrap and destroy remove clone template files

Fixes: lp:1351004

Juju with the new flock implementation doesn't care, but forcibly destroying a local environment can leave the lock dirs around. Then if a downgrade is done, the older juju which still uses fslock thinks the lock is still held and won't start containers. This fix removes any lock files when local provider is bootstrapped and destroyed.
Merge pull request #427 from wallyworld/clone-template-flock

Clone template flock

Fixes lp:1311668

Use flock to serialise lxc template creation rather than juju/utils/fslock
Merge pull request #507 from wallyworld/clone-template-flock-master

Clone template flock master

Forward port pull requests 427 and 452

Clone template flock

Fixes lp:1311668, lp:1351004

Use flock to serialise lxc template creation rather than juju/utils/fslock