Fix: improve API error responses from os-hosts extension

Modify responses to include the actual host instead of %(host)s.

Resolves bug 1154117.

Change-Id: Ic680403bdf1cb1fc1ac184352f486390fb04a195
Make conductor's quota methods pass project_id properly

Commit 652a487ed9daba9ae97f7df77ae35720322d1af3 added a workaround for
project_id on conductor's quota methods. This fully plumbs project_id
through to the manager (and thus the quota implementation) and removes
the tests that verify the workaround.

Fixes bug 1153795

Change-Id: I7cd5e3de39acfaba7831892aff6c754569c8e1bf
Merge "Fix: improve API error responses from os-hosts extension"
Merge "Make conductor's quota methods pass project_id properly"
Merge remote-tracking branch 'm_src_repo/master' into build-temp