Tune up mod_wsgi settings in example configuration
Tune up mod_wsgi settings in example configuration

Explicitly set mod-wsgi process-group to ceilometer-api in sample
This gives the process a good name in process listings.

Set number of process and threads to two and ten respectively. This
represents a reasonable setting to achieve moderate levels of
concurrency.

Change-Id: Iada6126cb525d597cc385c2d63e6228ef08d55a7

cernops/ceilometer,Juniper/ceilometer,pczerkas/aodh,redhat-openstack/ceilometer,eayunstack/ceilometer,pkilambi/ceilometer,r-mibu/ceilometer,m1093782566/openstack_org_ceilometer,eayunstack/ceilometer,m1093782566/openstack_org_ceilometer,isyippee/ceilometer,sileht/aodh,redhat-openstack/ceilometer,MisterPup/Ceilometer-Juno-Extension,idegtiarov/ceilometer,ityaptin/ceilometer,pkilambi/ceilometer,ityaptin/ceilometer,fabian4/ceilometer,Juniper/ceilometer,r-mibu/ceilometer,mathslinux/ceilometer,maestro-hybrid-cloud/ceilometer,froyobin/ceilometer,sileht/aodh,isyippee/ceilometer,MisterPup/Ceilometer-Juno-Extension,chungg/aodh,maestro-hybrid-cloud/ceilometer,pczerkas/aodh,cernops/ceilometer,openstack/ceilometer,fabian4/ceilometer,openstack/aodh,idegtiarov/ceilometer,froyobin/ceilometer,chungg/aodh,openstack/aodh,mathslinux/ceilometer,openstack/ceilometer