Merge lp://staging/~kelvin.li/rnr-server/log-enhancement into lp://staging/rnr-server

LGTM.

Just a comment about something that was introduced earlier: I find RNR_HOST_DIR name a bit misleading, if I gather that correctly it's a dir to place the launchpadlib cache dir mostly, so maybe we can rename it to better reflect that.

The attempt to merge lp:~kelvin.li/rnr-server/log-enhancement into lp:rnr-server failed. Below is the output from the failed tests.

echo 'cleaning virtualenv...'
cleaning virtualenv...
rm -rf /mnt/tarmac/cache/rnr-server/merges/trunk/virtualenv
echo 'creating new virtualenv...'
creating new virtualenv...
virtualenv --clear --system-site-packages /mnt/tarmac/cache/rnr-server/merges/trunk/virtualenv
Not deleting /mnt/tarmac/cache/rnr-server/merges/trunk/virtualenv/bin
New python executable in /mnt/tarmac/cache/rnr-server/merges/trunk/virtualenv/bin/python
Installing setuptools, pip...done.
make sanitize-sourcedeps
make[1]: Entering directory `/mnt/tarmac/cache/rnr-server/merges/trunk'
sed -e '1,/# Dependencies/d;s/^rnr-server/./g;s/bazaar.isd/bazaar.launchpad.net/g' config-manager.txt > config-manager.txt.tmp
make[1]: Leaving directory `/mnt/tarmac/cache/rnr-server/merges/trunk'
make CONFIGMANAGER=config-manager.txt.tmp build
make[1]: Entering directory `/mnt/tarmac/cache/rnr-server/merges/trunk'
/usr/lib/config-manager/cm.py update config-manager.txt.tmp
make[1]: Leaving directory `/mnt/tarmac/cache/rnr-server/merges/trunk'
touch branches/last_build
[ -d branches/wheels ] && (cd branches/wheels && bzr pull) || (bzr branch lp:~ubuntuone-pqm-team/rnr-server/dependencies branches/wheels)
bzr version-info --format=python > lib/versioninfo.py
/mnt/tarmac/cache/rnr-server/merges/trunk/virtualenv/bin/python /mnt/tarmac/cache/rnr-server/merges/trunk/virtualenv/bin/pip install --find-links=branches/wheels --no-index -r requirements.txt
Ignoring indexes: https://pypi.python.org/simple/
Downloading/unpacking amqp==1.4.5 (from -r requirements.txt (line 1))
Downloading/unpacking django==1.6.10 (from -r requirements.txt (line 2))
Downloading/unpacking django-openid-auth==0.6 (from -r requirements.txt (line 3))
Downloading/unpacking django-pgtools==0.2 (from -r requirements.txt (line 4))
Downloading/unpacking django-preflight==0.1.5 (from -r requirements.txt (line 5))
Requirement already satisfied (use --upgrade to upgrade): python-openid==2.2.5 in /usr/lib/python2.7/dist-packages (from -r requirements.txt (line 7))
Downloading/unpacking oauthlib==0.6.3 (from -r requirements.txt (line 8))
Requirement already satisfied (use --upgrade to upgrade): oops==0.0.13 in /usr/lib/pymodules/python2.7 (from -r requirements.txt (line 9))
Requirement already satisfied (use --upgrade to upgrade): oops-amqp==0.0.7 in /usr/lib/python2.7/dist-packages (from -r requirements.txt (line 10))
Downloading/unpacking oops-datedir-repo==0.0.20 (from -r requirements.txt (line 11))
Downloading/unpacking oops-dictconfig==0.0.4 (from -r requirements.txt (line 12))
Downloading/unpacking oops-wsgi==0.0.11 (from -r requirements.txt (line 13))
Downloading/unpacking requests-oauthlib==0.5.0 (from -r requirements.txt (line 15))
Downloading/unpacking south==1.0.2 (from -r requirements.txt (line 16))
Downloading/unpacking txstatsd==1.0.0 (from -r requirements.txt (line 17))
Downloading/unpacking whitenoise==2.0.4 (from -r requirements.txt (line 18))
Downloading/unpacking gunicorn==19.3.0 (from -r requirements.txt (line 19))
Downloading/unpacking rnrclient (from -r requirements.txt (line 21))
Do...