Change to use monasca everywhere

Change packages from com.hpcloud.mon to monasca.api

Rename service from mon-api to monasca-api. Move config file
to /etc/monasca, jar to /opt/monasca

Renamed files from mon- to monasca-

Use the monasca group.  Required so API can write to
/var/log/monasca and read config file in /etc/monasca

Change user from mon_api to monasca_api

Change-Id: Idaefe138629595507f3d38a533381408cc6f32e3