Add async operations framework

As a side effect, this commit also siginficantly reduces the response parsing
overhead in the client.

Signed-off-by: Tycho Andersen <tycho.andersen@canonical.com>
Add a 404 catch-all with our response

In addition to setting the 404 error code in the header, we need to also
respond with our json-style error messages reporting a 404.

Signed-off-by: Tycho Andersen <tycho.andersen@canonical.com>
Add /1.0/containers/<name> to rest api

Signed-off-by: Tycho Andersen <tycho.andersen@canonical.com>
Switch the operation url format back

Signed-off-by: Tycho Andersen <tycho.andersen@canonical.com>
test: don't do a shallow fetch for signoff check

If the user's PR doesn't have the current lxc/master commit in its history,
this check fails miserably since the shallow fetch won't have whatever patch
their branch is based on. We should instead fetch all the history, so a branch
from any commit checks correctly.

Signed-off-by: Tycho Andersen <tycho.andersen@canonical.com>
Merge pull request #69 from tych0/operation-ops

Operation ops