Ignore local folder
Ignore local folder

We currently ignore example files in dashboard/local. We should just ignore
the entire folder and exempt those files. This would allow developers and
operators to add content to the folder without accidentally committing it
upstream.

Change-Id: I2fe40af96ee62d85dd01e279485ce7f392a50a03
Closes-Bug: #1546218

sandvine/horizon,django-leonardo/horizon,dan1/horizon-x509,sandvine/horizon,redhat-openstack/horizon,dan1/horizon-x509,gerrive/horizon,NeCTAR-RC/horizon,redhat-openstack/horizon,BiznetGIO/horizon,openstack/horizon,noironetworks/horizon,bigswitch/horizon,bac/horizon,redhat-openstack/horizon,redhat-openstack/horizon,sandvine/horizon,gerrive/horizon,wolverineav/horizon,Mirantis/mos-horizon,dan1/horizon-x509,bac/horizon,Mirantis/mos-horizon,coreycb/horizon,noironetworks/horizon,bac/horizon,coreycb/horizon,bigswitch/horizon,django-leonardo/horizon,NeCTAR-RC/horizon,bac/horizon,wolverineav/horizon,BiznetGIO/horizon,django-leonardo/horizon,BiznetGIO/horizon,davidcusatis/horizon,ChameleonCloud/horizon,openstack/horizon,noironetworks/horizon,django-leonardo/horizon,NeCTAR-RC/horizon,ChameleonCloud/horizon,yeming233/horizon,sandvine/horizon,dan1/horizon-x509,bigswitch/horizon,bigswitch/horizon,openstack/horizon,noironetworks/horizon,gerrive/horizon,yeming233/horizon,davidcusatis/horizon,davidcusatis/horizon,wolverineav/horizon,coreycb/horizon,davidcusatis/horizon,Mirantis/mos-horizon,NeCTAR-RC/horizon,ChameleonCloud/horizon,openstack/horizon,yeming233/horizon,Mirantis/mos-horizon,coreycb/horizon,ChameleonCloud/horizon,gerrive/horizon,yeming233/horizon,BiznetGIO/horizon,wolverineav/horizon